Merge remote-tracking branch 'upstream/dev' into dev

2015-03-07 21:54:37 +01:00 · 2015-03-07 21:54:37 +01:00 · 76a499313f
parent 315d1a1696 acf0df3aad
commit 76a499313f
46 changed files with 3485 additions and 89 deletions
--- a/.travis.yml
+++ b/.travis.yml
@ -0,0 +1,21 @@
+language: cpp
+before_install:
+- sudo apt-get install -y python-serial srecord
+install:
+- wget https://github.com/GeorgeHahn/nodemcu-firmware/raw/travis/tools/esp-open-sdk.tar.gz -O tools/esp-open-sdk.tar.gz
+- tar -zxvf tools/esp-open-sdk.tar.gz
+- export PATH=$PATH:$PWD/esp-open-sdk/sdk:$PWD/esp-open-sdk/xtensa-lx106-elf/bin
+script:
+- make all
+- cd bin/
+- file_name="nodemcu-firmware_v${TRAVIS_TAG}.${TRAVIS_BUILD_NUMBER}.bin"
+- srec_cat -output ${file_name} -binary 0x00000.bin -binary -fill 0xff 0x00000 0x10000 0x10000.bin -binary -offset 0x10000
+deploy:
+  provider: releases
+  api_key:
+    secure: Swecz5lWvsuSbchSbVQ1rmCPN9nQIN5p/HlZNIEdEgAgnoLcJxRV4P8poVTB37jiA8Pck+8x2nWXpg74Rqik0i3KlPNvDfg5o4rIazWLNs4bc1Tbcpt44XAzFKKLYnDnWQUGcqjk7BcAXuNAF2X/fPBCVhFbHVg3Z7cDb32RsNw=
+  file: "$TRAVIS_BUILD_DIR/bin/${file_name}"
+  skip_cleanup: true
+  on:
+    tags: true
+    repo: nodemcu/nodemcu-firmware
--- a/README.md
+++ b/README.md
@ -1,5 +1,8 @@
-# **NodeMcu** #
+# **NodeMCU** #
 version 0.9.5
+
+[![Build Status](https://travis-ci.org/nodemcu/nodemcu-firmware.svg)](https://travis-ci.org/nodemcu/nodemcu-firmware)
+
 ###A lua based firmware for wifi-soc esp8266
 Build on [ESP8266 sdk 0.9.5](http://bbs.espressif.com/viewtopic.php?f=5&t=154)<br />
 Lua core based on [eLua project](http://www.eluaproject.net/)<br />
@ -7,24 +10,26 @@ File system based on [spiffs](https://github.com/pellepl/spiffs)<br />
 Open source development kit for NodeMCU [nodemcu-devkit](https://github.com/nodemcu/nodemcu-devkit)<br />
 Flash tool for NodeMCU [nodemcu-flasher](https://github.com/nodemcu/nodemcu-flasher)<br />

-wiki: [nodemcu wiki](https://github.com/nodemcu/nodemcu-firmware/wiki)<br />
-api: [nodemcu api](https://github.com/nodemcu/nodemcu-firmware/wiki/nodemcu_api_en)<br />
+wiki: [NodeMCU wiki](https://github.com/nodemcu/nodemcu-firmware/wiki)<br />
+api: [NodeMCU api](https://github.com/nodemcu/nodemcu-firmware/wiki/nodemcu_api_en)<br />
 home: [nodemcu.com](http://www.nodemcu.com)<br />
 bbs: [Chinese bbs](http://bbs.nodemcu.com)<br />
+docs: [NodeMCU docs](http://www.nodemcu.com/docs/)<br />
 Tencent QQ group: 309957875<br />

 # Summary
 - Easy to access wireless router
- Based on Lua 5.1.4 (without *io, math, debug, os* module.)
+- Based on Lua 5.1.4 (without *debug, os* module.)
 - Event-Drive programming preferred.
- Build-in file, timer, pwm, i2c, spi, 1-wire, net, mqtt, gpio, wifi, adc, uart and system api.
+- Build-in file, timer, pwm, i2c, spi, 1-wire, net, mqtt, coap, gpio, wifi, adc, uart and system api.
 - GPIO pin re-mapped, use the index to access gpio, i2c, pwm.

 # To Do List (pull requests are very welcomed)
+- loadable c module
 - fix wifi smart connect
 - add spi module (done)
 - add mqtt module (done)
- add coap module (in coap branch)
+- add coap module (done)
 - cross compiler (done)

 # Change log
@ -98,15 +103,19 @@ build pre_build bin.
 #### [*] D0(GPIO16) can only be used as gpio read/write. no interrupt supported. no pwm/i2c/ow supported.

 #Build option
-####file ./app/include/user_config.h
+####file ./app/include/user_modules.h
 ```c
-// #define FLASH_512K
-// #define FLASH_1M
-// #define FLASH_2M
-// #define FLASH_4M
-#define FLASH_AUTOSIZE
-...
+#define LUA_USE_BUILTIN_STRING    // for string.xxx()
+#define LUA_USE_BUILTIN_TABLE   // for table.xxx()
+#define LUA_USE_BUILTIN_COROUTINE // for coroutine.xxx()
+#define LUA_USE_BUILTIN_MATH    // for math.xxx(), partially work
+// #define LUA_USE_BUILTIN_IO       // for io.xxx(), partially work
+
+// #define LUA_USE_BUILTIN_OS     // for os.xxx(), not work
+// #define LUA_USE_BUILTIN_DEBUG    // for debug.xxx(), not work
+
 #define LUA_USE_MODULES
+
 #ifdef LUA_USE_MODULES
 #define LUA_USE_MODULES_NODE
 #define LUA_USE_MODULES_FILE
@ -115,15 +124,17 @@ build pre_build bin.
 #define LUA_USE_MODULES_NET
 #define LUA_USE_MODULES_PWM
 #define LUA_USE_MODULES_I2C
+#define LUA_USE_MODULES_SPI
 #define LUA_USE_MODULES_TMR
 #define LUA_USE_MODULES_ADC
 #define LUA_USE_MODULES_UART
 #define LUA_USE_MODULES_OW
 #define LUA_USE_MODULES_BIT
+#define LUA_USE_MODULES_MQTT
+// #define LUA_USE_MODULES_COAP     // need about 4k more ram for now
+#define LUA_USE_MODULES_U8G
 #define LUA_USE_MODULES_WS2812
 #endif /* LUA_USE_MODULES */
-...
-// LUA_NUMBER_INTEGRAL
 ```

 #Flash the firmware
--- a/app/.gitignore
+++ b/app/.gitignore
@ -1,2 +1,3 @@
 *.output*
+mapfile
 !.gitignore
--- a/app/Makefile
+++ b/app/Makefile
@ -30,6 +30,7 @@ SUBDIRS=    \
 	platform	\
 	libc 	\
 	lua 	\
+	coap	\
 	mqtt	\
 	u8glib  \
 	smart 	\
@ -77,6 +78,7 @@ COMPONENTS_eagle.app.v6 = \
 	platform/libplatform.a	\
 	libc/liblibc.a 	\
 	lua/liblua.a 	\
+	coap/coap.a 	\
 	mqtt/mqtt.a 	\
 	u8glib/u8glib.a \
 	smart/smart.a 	\
@ -106,7 +108,8 @@ LINKFLAGS_eagle.app.v6 = \
 	-lsmartconfig	\
 	-lssl	\
 	$(DEP_LIBS_eagle.app.v6)					\
-	-Wl,--end-group
+	-Wl,--end-group			\
+	-lm

 DEPENDS_eagle.app.v6 = \
                $(LD_FILE) \
--- a/app/coap/LICENSE.txt
+++ b/app/coap/LICENSE.txt
@ -0,0 +1,20 @@
+Copyright (c) 2013 Toby Jaffey <toby@1248.io>
+			  2015 Zeroday Hong <zeroday@nodemcu.com> nodemcu.com
+
+Permission is hereby granted, free of charge, to any person obtaining a copy
+of this software and associated documentation files (the "Software"), to deal
+in the Software without restriction, including without limitation the rights
+to use, copy, modify, merge, publish, distribute, sublicense, and/or sell
+copies of the Software, and to permit persons to whom the Software is
+furnished to do so, subject to the following conditions:
+
+The above copyright notice and this permission notice shall be included in
+all copies or substantial portions of the Software.
+
+THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
+IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
+FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
+AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
+LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING FROM,
+OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS IN
+THE SOFTWARE.
--- a/app/coap/Makefile
+++ b/app/coap/Makefile
@ -0,0 +1,45 @@
+
+#############################################################
+# Required variables for each makefile
+# Discard this section from all parent makefiles
+# Expected variables (with automatic defaults):
+#   CSRCS (all "C" files in the dir)
+#   SUBDIRS (all subdirs with a Makefile)
+#   GEN_LIBS - list of libs to be generated ()
+#   GEN_IMAGES - list of images to be generated ()
+#   COMPONENTS_xxx - a list of libs/objs in the form
+#     subdir/lib to be extracted and rolled up into
+#     a generated lib/image xxx.a ()
+#
+ifndef PDIR
+GEN_LIBS = coap.a
+endif
+
+#############################################################
+# Configuration i.e. compile options etc.
+# Target specific stuff (defines etc.) goes in here!
+# Generally values applying to a tree are captured in the
+#   makefile at its root level - these are then overridden
+#   for a subtree within the makefile rooted therein
+#
+#DEFINES += 
+
+#############################################################
+# Recursion Magic - Don't touch this!!
+#
+# Each subtree potentially has an include directory
+#   corresponding to the common APIs applicable to modules
+#   rooted at that subtree. Accordingly, the INCLUDE PATH
+#   of a module can only contain the include directories up
+#   its parent path, and not its siblings
+#
+# Required for each makefile to inherit from the parent
+#
+
+INCLUDES := $(INCLUDES) -I $(PDIR)include
+INCLUDES += -I ./
+INCLUDES += -I ../libc
+INCLUDES += -I ../lua
+PDIR := ../$(PDIR)
+sinclude $(PDIR)Makefile
+
--- a/app/coap/coap.c
+++ b/app/coap/coap.c
@ -0,0 +1,555 @@
+#include "user_config.h"
+#include "c_stdio.h"
+#include "c_string.h"
+#include "coap.h"
+#include "uri.h"
+
+extern void endpoint_setup(void);
+extern const coap_endpoint_t endpoints[];
+
+#ifdef COAP_DEBUG
+void coap_dumpHeader(coap_header_t *hdr)
+{
+    c_printf("Header:\n");
+    c_printf("  ver  0x%02X\n", hdr->ver);
+    c_printf("  t    0x%02X\n", hdr->ver);
+    c_printf("  tkl  0x%02X\n", hdr->tkl);
+    c_printf("  code 0x%02X\n", hdr->code);
+    c_printf("  id   0x%02X%02X\n", hdr->id[0], hdr->id[1]);
+}
+
+void coap_dump(const uint8_t *buf, size_t buflen, bool bare)
+{
+    if (bare)
+    {
+        while(buflen--)
+            c_printf("%02X%s", *buf++, (buflen > 0) ? " " : "");
+    }
+    else
+    {
+        c_printf("Dump: ");
+        while(buflen--)
+            c_printf("%02X%s", *buf++, (buflen > 0) ? " " : "");
+        c_printf("\n");
+    }
+}
+#endif
+
+int coap_parseHeader(coap_header_t *hdr, const uint8_t *buf, size_t buflen)
+{
+    if (buflen < 4)
+        return COAP_ERR_HEADER_TOO_SHORT;
+    hdr->ver = (buf[0] & 0xC0) >> 6;
+    if (hdr->ver != 1)
+        return COAP_ERR_VERSION_NOT_1;
+    hdr->t = (buf[0] & 0x30) >> 4;
+    hdr->tkl = buf[0] & 0x0F;
+    hdr->code = buf[1];
+    hdr->id[0] = buf[2];
+    hdr->id[1] = buf[3];
+    return 0;
+}
+
+int coap_buildHeader(const coap_header_t *hdr, uint8_t *buf, size_t buflen)
+{
+    // build header
+    if (buflen < 4)
+        return COAP_ERR_BUFFER_TOO_SMALL;
+
+    buf[0] = (hdr->ver & 0x03) << 6;
+    buf[0] |= (hdr->t & 0x03) << 4;
+    buf[0] |= (hdr->tkl & 0x0F);
+    buf[1] = hdr->code;
+    buf[2] = hdr->id[0];
+    buf[3] = hdr->id[1];
+    return 4;
+}
+
+int coap_parseToken(coap_buffer_t *tokbuf, const coap_header_t *hdr, const uint8_t *buf, size_t buflen)
+{
+    if (hdr->tkl == 0)
+    {
+        tokbuf->p = NULL;
+        tokbuf->len = 0;
+        return 0;
+    }
+    else
+    if (hdr->tkl <= 8)
+    {
+        if (4 + hdr->tkl > buflen)
+            return COAP_ERR_TOKEN_TOO_SHORT;   // tok bigger than packet
+        tokbuf->p = buf+4;  // past header
+        tokbuf->len = hdr->tkl;
+        return 0;
+    }
+    else
+    {
+        // invalid size
+        return COAP_ERR_TOKEN_TOO_SHORT;
+    }
+}
+
+int coap_buildToken(const coap_buffer_t *tokbuf, const coap_header_t *hdr, uint8_t *buf, size_t buflen)
+{
+    // inject token
+    uint8_t *p;
+    if (buflen < 4 + hdr->tkl)
+        return COAP_ERR_BUFFER_TOO_SMALL;
+    p = buf + 4;
+    if ((hdr->tkl > 0) && (hdr->tkl != tokbuf->len))
+        return COAP_ERR_UNSUPPORTED;
+    
+    if (hdr->tkl > 0)
+        c_memcpy(p, tokbuf->p, hdr->tkl);
+
+    // http://tools.ietf.org/html/draft-ietf-core-coap-18#section-3.1
+    // inject options
+    return hdr->tkl;
+}
+
+// advances p
+int coap_parseOption(coap_option_t *option, uint16_t *running_delta, const uint8_t **buf, size_t buflen)
+{
+    const uint8_t *p = *buf;
+    uint16_t len, delta;
+    uint8_t headlen = 1;
+
+    if (buflen < headlen) // too small
+        return COAP_ERR_OPTION_TOO_SHORT_FOR_HEADER;
+
+    delta = (p[0] & 0xF0) >> 4;
+    len = p[0] & 0x0F;
+
+    // These are untested and may be buggy
+    if (delta == 13)
+    {
+        headlen++;
+        if (buflen < headlen)
+            return COAP_ERR_OPTION_TOO_SHORT_FOR_HEADER;
+        delta = p[1] + 13;
+        p++;
+    }
+    else
+    if (delta == 14)
+    {
+        headlen += 2;
+        if (buflen < headlen)
+            return COAP_ERR_OPTION_TOO_SHORT_FOR_HEADER;
+        delta = ((p[1] << 8) | p[2]) + 269;
+        p+=2;
+    }
+    else
+    if (delta == 15)
+        return COAP_ERR_OPTION_DELTA_INVALID;
+
+    if (len == 13)
+    {
+        headlen++;
+        if (buflen < headlen)
+            return COAP_ERR_OPTION_TOO_SHORT_FOR_HEADER;
+        len = p[1] + 13;
+        p++;
+    }
+    else
+    if (len == 14)
+    {
+        headlen += 2;
+        if (buflen < headlen)
+            return COAP_ERR_OPTION_TOO_SHORT_FOR_HEADER;
+        len = ((p[1] << 8) | p[2]) + 269;
+        p+=2;
+    }
+    else
+    if (len == 15)
+        return COAP_ERR_OPTION_LEN_INVALID;
+
+    if ((p + 1 + len) > (*buf + buflen))
+        return COAP_ERR_OPTION_TOO_BIG;
+
+    //printf("option num=%d\n", delta + *running_delta);
+    option->num = delta + *running_delta;
+    option->buf.p = p+1;
+    option->buf.len = len;
+    //coap_dump(p+1, len, false);
+
+    // advance buf
+    *buf = p + 1 + len;
+    *running_delta += delta;
+
+    return 0;
+}
+
+// http://tools.ietf.org/html/draft-ietf-core-coap-18#section-3.1
+int coap_parseOptionsAndPayload(coap_option_t *options, uint8_t *numOptions, coap_buffer_t *payload, const coap_header_t *hdr, const uint8_t *buf, size_t buflen)
+{
+    size_t optionIndex = 0;
+    const uint8_t *p = buf + 4 + hdr->tkl;
+    const uint8_t *end = buf + buflen;
+    int rc;
+    uint16_t delta = 0;
+    if (p > end)
+        return COAP_ERR_OPTION_OVERRUNS_PACKET;   // out of bounds
+
+    //coap_dump(p, end - p);
+
+    // 0xFF is payload marker
+    while((optionIndex < *numOptions) && (p < end) && (*p != 0xFF))
+    {
+        if (0 != (rc = coap_parseOption(&options[optionIndex], &delta, &p, end-p)))
+            return rc;
+        optionIndex++;
+    }
+    *numOptions = optionIndex;
+
+    if (p+1 < end && *p == 0xFF)  // payload marker
+    {
+        payload->p = p+1;
+        payload->len = end-(p+1);
+    }
+    else
+    {
+        payload->p = NULL;
+        payload->len = 0;
+    }
+
+    return 0;
+}
+
+int coap_buildOptionHeader(unsigned short optDelta, size_t length, uint8_t *buf, size_t buflen)
+{
+    int n = 0;
+    uint8_t *p = buf;
+    uint8_t len, delta = 0;
+
+    if (buflen < 5)
+        return COAP_ERR_BUFFER_TOO_SMALL;
+
+    coap_option_nibble(optDelta, &delta);
+    coap_option_nibble(length, &len);
+
+    *p++ = (0xFF & (delta << 4 | len));
+    n++;
+    if (delta == 13)
+    {
+        *p++ = (optDelta - 13);
+        n++;
+    }
+    else
+    if (delta == 14)
+    {
+        *p++ = ((optDelta-269) >> 8);
+        *p++ = (0xFF & (optDelta-269));
+        n+=2;
+    }
+    if (len == 13)
+    {
+        *p++ = (length - 13);
+        n++;
+    }
+    else
+    if (len == 14)
+    {
+        *p++ = (length >> 8);
+        *p++ = (0xFF & (length-269));
+        n+=2;
+    }
+    return n;
+}
+
+#ifdef COAP_DEBUG
+void coap_dumpOptions(coap_option_t *opts, size_t numopt)
+{
+    size_t i;
+    c_printf(" Options:\n");
+    for (i=0;i<numopt;i++)
+    {
+        c_printf("  0x%02X [ ", opts[i].num);
+        coap_dump(opts[i].buf.p, opts[i].buf.len, true);
+        c_printf(" ]\n");
+    }
+}
+
+void coap_dumpPacket(coap_packet_t *pkt)
+{
+    coap_dumpHeader(&pkt->hdr);
+    coap_dumpOptions(pkt->opts, pkt->numopts);
+    c_printf("Payload: ");
+    coap_dump(pkt->payload.p, pkt->payload.len, true);
+    c_printf("\n");
+}
+#endif
+
+int coap_parse(coap_packet_t *pkt, const uint8_t *buf, size_t buflen)
+{
+    int rc;
+
+    // coap_dump(buf, buflen, false);
+
+    if (0 != (rc = coap_parseHeader(&pkt->hdr, buf, buflen)))
+        return rc;
+//    coap_dumpHeader(&hdr);
+    if (0 != (rc = coap_parseToken(&pkt->tok, &pkt->hdr, buf, buflen)))
+        return rc;
+    pkt->numopts = MAXOPT;
+    if (0 != (rc = coap_parseOptionsAndPayload(pkt->opts, &(pkt->numopts), &(pkt->payload), &pkt->hdr, buf, buflen)))
+        return rc;
+//    coap_dumpOptions(opts, numopt);
+    return 0;
+}
+
+// options are always stored consecutively, so can return a block with same option num
+const coap_option_t * coap_findOptions(const coap_packet_t *pkt, uint8_t num, uint8_t *count)
+{
+    // FIXME, options is always sorted, can find faster than this
+    size_t i;
+    const coap_option_t *first = NULL;
+    *count = 0;
+    for (i=0;i<pkt->numopts;i++)
+    {
+        if (pkt->opts[i].num == num)
+        {
+            if (NULL == first)
+                first = &pkt->opts[i];
+            (*count)++;
+        }
+        else
+        {
+            if (NULL != first)
+                break;
+        }
+    }
+    return first;
+}
+
+int coap_buffer_to_string(char *strbuf, size_t strbuflen, const coap_buffer_t *buf)
+{
+    if (buf->len+1 > strbuflen)
+        return COAP_ERR_BUFFER_TOO_SMALL;
+    c_memcpy(strbuf, buf->p, buf->len);
+    strbuf[buf->len] = 0;
+    return 0;
+}
+
+int coap_build(uint8_t *buf, size_t *buflen, const coap_packet_t *pkt)
+{
+    size_t opts_len = 0, hdr_len = 0, tok_len = 0;
+    size_t i;
+    uint8_t *p = buf;
+    size_t left = *buflen;
+    uint16_t running_delta = 0;
+
+    hdr_len = coap_buildHeader(&(pkt->hdr), buf, *buflen);
+    p += hdr_len;
+    left -= hdr_len;
+
+    tok_len = coap_buildToken(&(pkt->tok), &(pkt->hdr), buf, *buflen);
+    p += tok_len;
+    left -= tok_len;
+
+    for (i=0;i<pkt->numopts;i++)
+    {
+        uint8_t len, delta = 0;
+        uint16_t optDelta = 0;
+        int rc = 0;
+
+        if (p-buf > *buflen)
+             return COAP_ERR_BUFFER_TOO_SMALL;
+        optDelta = pkt->opts[i].num - running_delta;
+
+        rc = coap_buildOptionHeader(optDelta, pkt->opts[i].buf.len, p, left);
+        p += rc;
+        left -= rc;
+
+        c_memcpy(p, pkt->opts[i].buf.p, pkt->opts[i].buf.len);
+        p += pkt->opts[i].buf.len;
+        left -= pkt->opts[i].buf.len;
+        running_delta = pkt->opts[i].num;
+    }
+
+    opts_len = (p - buf) - 4;   // number of bytes used by options
+
+    if (pkt->payload.len > 0)
+    {
+        if (*buflen < 4 + 1 + pkt->payload.len + opts_len)
+            return COAP_ERR_BUFFER_TOO_SMALL;
+        buf[4 + opts_len] = 0xFF;  // payload marker
+        c_memcpy(buf+5 + opts_len, pkt->payload.p, pkt->payload.len);
+        *buflen = opts_len + 5 + pkt->payload.len;
+    }
+    else
+        *buflen = opts_len + 4;
+    return 0;
+}
+
+void coap_option_nibble(uint16_t value, uint8_t *nibble)
+{
+    if (value<13)
+    {
+        *nibble = (0xFF & value);
+    }
+    else
+    if (((uint32_t)value)<=0xFF+13)
+    {
+        *nibble = 13;
+    } else if (((uint32_t)value) -269 <=0xFFFF)
+    {
+        *nibble = 14;
+    }
+}
+
+int coap_make_response(coap_rw_buffer_t *scratch, coap_packet_t *pkt, const uint8_t *content, size_t content_len, uint8_t msgid_hi, uint8_t msgid_lo, const coap_buffer_t* tok, coap_responsecode_t rspcode, coap_content_type_t content_type)
+{
+    pkt->hdr.ver = 0x01;
+    pkt->hdr.t = COAP_TYPE_ACK;
+    pkt->hdr.tkl = 0;
+    pkt->hdr.code = rspcode;
+    pkt->hdr.id[0] = msgid_hi;
+    pkt->hdr.id[1] = msgid_lo;
+    pkt->numopts = 0;
+
+    // need token in response
+    if (tok) {
+        pkt->hdr.tkl = tok->len;
+        pkt->tok = *tok;
+    }
+
+    // safe because 1 < MAXOPT
+    pkt->opts[0].num = COAP_OPTION_CONTENT_FORMAT;
+    pkt->opts[0].buf.p = scratch->p;
+    if (scratch->len < 2)
+        return COAP_ERR_BUFFER_TOO_SMALL;
+    scratch->p[0] = ((uint16_t)content_type & 0xFF00) >> 8;
+    scratch->p[1] = ((uint16_t)content_type & 0x00FF);
+    pkt->opts[0].buf.len = 2;
+    pkt->payload.p = content;
+    pkt->payload.len = content_len;
+    return 0;
+}
+
+
+unsigned int coap_encode_var_bytes(unsigned char *buf, unsigned int val) {
+  unsigned int n, i;
+
+  for (n = 0, i = val; i && n < sizeof(val); ++n)
+    i >>= 8;
+
+  i = n;
+  while (i--) {
+    buf[i] = val & 0xff;
+    val >>= 8;
+  }
+
+  return n;
+}
+
+static uint8_t _token_data[4]={'n','o','d','e'};
+coap_buffer_t the_token = { _token_data, 4 };
+static unsigned short message_id;
+
+int coap_make_request(coap_rw_buffer_t *scratch, coap_packet_t *pkt, coap_msgtype_t t, coap_method_t m, coap_uri_t *uri, const uint8_t *payload, size_t payload_len)
+{
+    int res;
+    pkt->hdr.ver = 0x01;
+    pkt->hdr.t = t;
+    pkt->hdr.tkl = 0;
+    pkt->hdr.code = m;
+    pkt->hdr.id[0] = (message_id >> 8) & 0xFF;  //msgid_hi;
+    pkt->hdr.id[1] = message_id & 0xFF; //msgid_lo;
+    message_id++;
+    NODE_DBG("message_id: %d.\n", message_id);
+    pkt->numopts = 0;
+
+    if (the_token.len) {
+        pkt->hdr.tkl = the_token.len;
+        pkt->tok = the_token;
+    }
+
+    if (scratch->len < 2)   // TBD...
+        return COAP_ERR_BUFFER_TOO_SMALL;
+
+    uint8_t *saved = scratch->p;
+
+    /* split arg into Uri-* options */
+    // const char *addr = uri->host.s;
+    // if(uri->host.length && (c_strlen(addr) != uri->host.length || c_memcmp(addr, uri->host.s, uri->host.length) != 0)){
+    if(uri->host.length){
+        /* add Uri-Host */
+        // addr is destination address
+        pkt->opts[pkt->numopts].num = COAP_OPTION_URI_HOST;
+        pkt->opts[pkt->numopts].buf.p = uri->host.s;
+        pkt->opts[pkt->numopts].buf.len = uri->host.length;
+        pkt->numopts++;
+    }
+
+    if (uri->port != COAP_DEFAULT_PORT) {
+        pkt->opts[pkt->numopts].num = COAP_OPTION_URI_PORT;
+        res = coap_encode_var_bytes(scratch->p, uri->port); 
+        pkt->opts[pkt->numopts].buf.len = res;
+        pkt->opts[pkt->numopts].buf.p = scratch->p;
+        scratch->p += res;
+        scratch->len -= res;
+        pkt->numopts++;
+    }
+
+    if (uri->path.length) {
+        res = coap_split_path(scratch, pkt, uri->path.s, uri->path.length);
+    }
+
+    if (uri->query.length) {
+        res = coap_split_query(scratch, pkt, uri->query.s, uri->query.length);    
+    }
+
+    pkt->payload.p = payload;
+    pkt->payload.len = payload_len;
+    scratch->p = saved;     // save back the pointer.
+    return 0;
+}
+
+// FIXME, if this looked in the table at the path before the method then
+// it could more easily return 405 errors
+int coap_handle_req(coap_rw_buffer_t *scratch, const coap_packet_t *inpkt, coap_packet_t *outpkt)
+{
+    const coap_option_t *opt;
+    int i;
+    uint8_t count;
+    const coap_endpoint_t *ep = endpoints;
+
+    while(NULL != ep->handler)
+    {
+        if (ep->method != inpkt->hdr.code)
+            goto next;
+        if (NULL != (opt = coap_findOptions(inpkt, COAP_OPTION_URI_PATH, &count)))
+        {
+            // if (count != ep->path->count)
+            if ((count != ep->path->count ) && (count != ep->path->count + 1)) // +1 for /f/[function], /v/[variable]
+                goto next;
+            for (i=0;i<ep->path->count;i++)
+            {
+                if (opt[i].buf.len != c_strlen(ep->path->elems[i]))
+                    goto next;
+                if (0 != c_memcmp(ep->path->elems[i], opt[i].buf.p, opt[i].buf.len))
+                    goto next;
+            }
+            // pre-path match!
+            if (count==ep->path->count+1 && ep->user_entry == NULL)
+                goto next;
+            return ep->handler(ep, scratch, inpkt, outpkt, inpkt->hdr.id[0], inpkt->hdr.id[1]);
+        }
+next:
+        ep++;
+    }
+
+    coap_make_response(scratch, outpkt, NULL, 0, inpkt->hdr.id[0], inpkt->hdr.id[1], &inpkt->tok, COAP_RSPCODE_NOT_FOUND, COAP_CONTENTTYPE_NONE);
+
+    return 0;
+}
+
+void coap_setup(void)
+{
+    message_id = (unsigned short)rand();      // calculate only once
+}
+
+inline int
+check_token(coap_packet_t *pkt) {
+  return pkt->tok.len == the_token.len && c_memcmp(pkt->tok.p, the_token.p, the_token.len) == 0;
+}
--- a/app/coap/coap.h
+++ b/app/coap/coap.h
@ -0,0 +1,186 @@
+#ifndef COAP_H
+#define COAP_H 1
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include "c_stdint.h"
+#include "c_stddef.h"
+#include "lualib.h"
+#include "lauxlib.h"
+
+#define MAXOPT 16
+#define MAX_MESSAGE_SIZE 1152
+#define MAX_PAYLOAD_SIZE 1024
+#define MAX_REQUEST_SIZE 576
+#define MAX_REQ_SCRATCH_SIZE 60
+
+#define COAP_RESPONSE_CLASS(C) (((C) >> 5) & 0xFF)
+
+// http://tools.ietf.org/html/draft-ietf-core-coap-18#section-3
+typedef struct
+{
+    uint8_t ver;
+    uint8_t t;
+    uint8_t tkl;
+    uint8_t code;
+    uint8_t id[2];
+} coap_header_t;
+
+typedef struct
+{
+    const uint8_t *p;
+    size_t len;
+} coap_buffer_t;
+
+typedef struct
+{
+    uint8_t *p;
+    size_t len;
+} coap_rw_buffer_t;
+
+typedef struct
+{
+    uint8_t num;
+    coap_buffer_t buf;
+} coap_option_t;
+
+typedef struct
+{
+    coap_header_t hdr;
+    coap_buffer_t tok;
+    uint8_t numopts;
+    coap_option_t opts[MAXOPT];
+    coap_buffer_t payload;
+    coap_rw_buffer_t scratch;       // scratch->p = malloc(...) , and free it when done.
+} coap_packet_t;
+
+/////////////////////////////////////////
+
+//http://tools.ietf.org/html/draft-ietf-core-coap-18#section-12.2
+typedef enum
+{
+    COAP_OPTION_IF_MATCH = 1,
+    COAP_OPTION_URI_HOST = 3,
+    COAP_OPTION_ETAG = 4,
+    COAP_OPTION_IF_NONE_MATCH = 5,
+    COAP_OPTION_OBSERVE = 6,
+    COAP_OPTION_URI_PORT = 7,
+    COAP_OPTION_LOCATION_PATH = 8,
+    COAP_OPTION_URI_PATH = 11,
+    COAP_OPTION_CONTENT_FORMAT = 12,
+    COAP_OPTION_MAX_AGE = 14,
+    COAP_OPTION_URI_QUERY = 15,
+    COAP_OPTION_ACCEPT = 17,
+    COAP_OPTION_LOCATION_QUERY = 20,
+    COAP_OPTION_PROXY_URI = 35,
+    COAP_OPTION_PROXY_SCHEME = 39
+} coap_option_num_t;
+
+//http://tools.ietf.org/html/draft-ietf-core-coap-18#section-12.1.1
+typedef enum
+{
+    COAP_METHOD_GET = 1,
+    COAP_METHOD_POST = 2,
+    COAP_METHOD_PUT = 3,
+    COAP_METHOD_DELETE = 4
+} coap_method_t;
+
+//http://tools.ietf.org/html/draft-ietf-core-coap-18#section-12.1.1
+typedef enum
+{
+    COAP_TYPE_CON = 0,
+    COAP_TYPE_NONCON = 1,
+    COAP_TYPE_ACK = 2,
+    COAP_TYPE_RESET = 3
+} coap_msgtype_t;
+
+//http://tools.ietf.org/html/draft-ietf-core-coap-18#section-5.2
+//http://tools.ietf.org/html/draft-ietf-core-coap-18#section-12.1.2
+#define MAKE_RSPCODE(clas, det) ((clas << 5) | (det))
+typedef enum
+{
+    COAP_RSPCODE_CONTENT = MAKE_RSPCODE(2, 5),
+    COAP_RSPCODE_NOT_FOUND = MAKE_RSPCODE(4, 4),
+    COAP_RSPCODE_BAD_REQUEST = MAKE_RSPCODE(4, 0),
+    COAP_RSPCODE_CHANGED = MAKE_RSPCODE(2, 4)
+} coap_responsecode_t;
+
+//http://tools.ietf.org/html/draft-ietf-core-coap-18#section-12.3
+typedef enum
+{
+    COAP_CONTENTTYPE_NONE = -1, // bodge to allow us not to send option block
+    COAP_CONTENTTYPE_TEXT_PLAIN = 0,
+    COAP_CONTENTTYPE_APPLICATION_LINKFORMAT = 40,
+} coap_content_type_t;
+
+///////////////////////
+
+typedef enum
+{
+    COAP_ERR_NONE = 0,
+    COAP_ERR_HEADER_TOO_SHORT = 1,
+    COAP_ERR_VERSION_NOT_1 = 2,
+    COAP_ERR_TOKEN_TOO_SHORT = 3,
+    COAP_ERR_OPTION_TOO_SHORT_FOR_HEADER = 4,
+    COAP_ERR_OPTION_TOO_SHORT = 5,
+    COAP_ERR_OPTION_OVERRUNS_PACKET = 6,
+    COAP_ERR_OPTION_TOO_BIG = 7,
+    COAP_ERR_OPTION_LEN_INVALID = 8,
+    COAP_ERR_BUFFER_TOO_SMALL = 9,
+    COAP_ERR_UNSUPPORTED = 10,
+    COAP_ERR_OPTION_DELTA_INVALID = 11,
+} coap_error_t;
+
+///////////////////////
+typedef struct coap_endpoint_t coap_endpoint_t;
+
+typedef int (*coap_endpoint_func)(const coap_endpoint_t *ep, coap_rw_buffer_t *scratch, const coap_packet_t *inpkt, coap_packet_t *outpkt, uint8_t id_hi, uint8_t id_lo);
+#define MAX_SEGMENTS 3  // 2 = /foo/bar, 3 = /foo/bar/baz
+#define MAX_SEGMENTS_SIZE   16
+typedef struct
+{
+    int count;
+    const char *elems[MAX_SEGMENTS];
+} coap_endpoint_path_t;
+
+typedef struct coap_luser_entry coap_luser_entry;
+
+struct coap_luser_entry{
+    lua_State *L;
+    // int ref;
+    // char name[MAX_SEGMENTS_SIZE+1];         // +1 for string '\0'
+    const char *name;
+    coap_luser_entry *next;
+};
+
+struct coap_endpoint_t
+{
+    coap_method_t method;
+    coap_endpoint_func handler;
+    const coap_endpoint_path_t *path;
+    const char *core_attr;
+    coap_luser_entry *user_entry;
+};
+
+///////////////////////
+void coap_dumpPacket(coap_packet_t *pkt);
+int coap_parse(coap_packet_t *pkt, const uint8_t *buf, size_t buflen);
+int coap_buffer_to_string(char *strbuf, size_t strbuflen, const coap_buffer_t *buf);
+const coap_option_t *coap_findOptions(const coap_packet_t *pkt, uint8_t num, uint8_t *count);
+int coap_build(uint8_t *buf, size_t *buflen, const coap_packet_t *pkt);
+void coap_dump(const uint8_t *buf, size_t buflen, bool bare);
+int coap_make_response(coap_rw_buffer_t *scratch, coap_packet_t *pkt, const uint8_t *content, size_t content_len, uint8_t msgid_hi, uint8_t msgid_lo, const coap_buffer_t* tok, coap_responsecode_t rspcode, coap_content_type_t content_type);
+int coap_handle_req(coap_rw_buffer_t *scratch, const coap_packet_t *inpkt, coap_packet_t *outpkt);
+void coap_option_nibble(uint16_t value, uint8_t *nibble);
+void coap_setup(void);
+void endpoint_setup(void);
+
+int coap_buildOptionHeader(unsigned short optDelta, size_t length, uint8_t *buf, size_t buflen);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
--- a/app/coap/coap_client.c
+++ b/app/coap/coap_client.c
@ -0,0 +1,67 @@
+#include "user_config.h"
+#include "c_types.h"
+
+#include "coap.h"
+#include "hash.h"
+#include "node.h"
+
+extern coap_queue_t *gQueue;
+
+void coap_client_response_handler(char *data, unsigned short len, unsigned short size, const uint32_t ip, const uint32_t port)
+{
+  NODE_DBG("coap_client_response_handler is called.\n");
+  coap_packet_t pkt;
+  int rc;
+
+  if (0 != (rc = coap_parse(&pkt, data, len))){
+    NODE_DBG("Bad packet rc=%d\n", rc);
+  }
+  else
+  {
+#ifdef COAP_DEBUG
+    coap_dumpPacket(&pkt);
+#endif
+    /* check if this is a response to our original request */
+    if (!check_token(&pkt)) {
+      /* drop if this was just some message, or send RST in case of notification */
+      if (pkt.hdr.t == COAP_TYPE_CON || pkt.hdr.t == COAP_TYPE_NONCON){
+        // coap_send_rst(pkt);  // send RST response
+        // or, just ignore it.
+      }
+      goto end;
+    }
+
+    if (pkt.hdr.t == COAP_TYPE_RESET) {
+      NODE_DBG("got RST\n");
+      goto end;
+    }
+
+    coap_tid_t id = COAP_INVALID_TID;
+    coap_transaction_id(ip, port, &pkt, &id);
+    /* transaction done, remove the node from queue */
+    // stop timer
+    coap_timer_stop();
+    // remove the node
+    coap_remove_node(&gQueue, id);
+    // calculate time elapsed
+    coap_timer_update(&gQueue);
+    coap_timer_start(&gQueue);
+
+    if (COAP_RESPONSE_CLASS(pkt.hdr.code) == 2)
+    {
+      /* There is no block option set, just read the data and we are done. */
+      NODE_DBG("%d.%02d\t", (pkt.hdr.code >> 5), pkt.hdr.code & 0x1F);
+      NODE_DBG((char *)(pkt.payload.p));
+    }
+    else if (COAP_RESPONSE_CLASS(pkt.hdr.code) >= 4)
+    {
+      NODE_DBG("%d.%02d\t", (pkt.hdr.code >> 5), pkt.hdr.code & 0x1F);
+      NODE_DBG((char *)(pkt.payload.p));
+    }
+  }
+
+end:
+  if(!gQueue){ // if there is no node pending in the queue, disconnect from host.
+
+  }
+}
--- a/app/coap/coap_client.h
+++ b/app/coap/coap_client.h
@ -0,0 +1,14 @@
+#ifndef _COAP_SERVER_H
+#define _COAP_SERVER_H 1
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+size_t coap_server_respond(char *data, unsigned short len, unsigned short size);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
--- a/app/coap/coap_io.c
+++ b/app/coap/coap_io.c
@ -0,0 +1,71 @@
+#include "c_string.h"
+#include "coap_io.h"
+#include "node.h"
+#include "espconn.h"
+#include "coap_timer.h"
+
+extern coap_queue_t *gQueue;
+
+/* releases space allocated by PDU if free_pdu is set */
+coap_tid_t coap_send(struct espconn *pesp_conn, coap_pdu_t *pdu) {
+  coap_tid_t id = COAP_INVALID_TID;
+  uint32_t ip = 0, port = 0;
+  if ( !pesp_conn || !pdu )
+    return id;
+
+  espconn_sent(pesp_conn, (unsigned char *)(pdu->msg.p), pdu->msg.len);
+
+  if(pesp_conn->type == ESPCONN_TCP){
+    c_memcpy(&ip, pesp_conn->proto.tcp->remote_ip, sizeof(ip));
+    port = pesp_conn->proto.tcp->remote_port;
+  }else{
+    c_memcpy(&ip, pesp_conn->proto.udp->remote_ip, sizeof(ip));
+    port = pesp_conn->proto.udp->remote_port;
+  }
+  coap_transaction_id(ip, port, pdu->pkt, &id);
+  return id;
+}
+
+coap_tid_t coap_send_confirmed(struct espconn *pesp_conn, coap_pdu_t *pdu) {
+  coap_queue_t *node;
+  coap_tick_t diff;
+  uint32_t r;
+
+  node = coap_new_node();
+  if (!node) {
+    NODE_DBG("coap_send_confirmed: insufficient memory\n");
+    return COAP_INVALID_TID;
+  }
+
+  node->retransmit_cnt = 0;
+  node->id = coap_send(pesp_conn, pdu);
+  if (COAP_INVALID_TID == node->id) {
+    NODE_DBG("coap_send_confirmed: error sending pdu\n");
+    coap_free_node(node);
+    return COAP_INVALID_TID;
+  }
+  r = rand();
+
+  /* add randomized RESPONSE_TIMEOUT to determine retransmission timeout */
+  node->timeout = COAP_DEFAULT_RESPONSE_TIMEOUT * COAP_TICKS_PER_SECOND +
+    (COAP_DEFAULT_RESPONSE_TIMEOUT >> 1) *
+    ((COAP_TICKS_PER_SECOND * (r & 0xFF)) >> 8);
+
+  node->pconn = pesp_conn;
+  node->pdu = pdu;
+
+  /* Set timer for pdu retransmission. If this is the first element in
+   * the retransmission queue, the base time is set to the current
+   * time and the retransmission time is node->timeout. If there is
+   * already an entry in the sendqueue, we must check if this node is
+   * to be retransmitted earlier. Therefore, node->timeout is first
+   * normalized to the timeout and then inserted into the queue with
+   * an adjusted relative time.
+   */
+  coap_timer_stop();
+  coap_timer_update(&gQueue);
+  node->t = node->timeout;  
+  coap_insert_node(&gQueue, node);
+  coap_timer_start(&gQueue);
+  return node->id;
+}
--- a/app/coap/coap_io.h
+++ b/app/coap/coap_io.h
@ -0,0 +1,20 @@
+#ifndef _COAP_IO_H
+#define _COAP_IO_H 1
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include "espconn.h"
+#include "pdu.h"
+#include "hash.h"
+	
+coap_tid_t coap_send(struct espconn *pesp_conn, coap_pdu_t *pdu);
+
+coap_tid_t coap_send_confirmed(struct espconn *pesp_conn, coap_pdu_t *pdu);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
--- a/app/coap/coap_server.c
+++ b/app/coap/coap_server.c
@ -0,0 +1,53 @@
+#include "user_config.h"
+#include "c_types.h"
+
+#include "coap.h"
+
+size_t coap_server_respond(char *data, unsigned short len, unsigned short size)
+{
+  NODE_DBG("coap_server_respond is called.\n");
+  if(len>size){
+    NODE_DBG("len:%d, size:%d\n",len,size);
+    return 0;
+  }
+  size_t rsplen = size;
+  coap_packet_t pkt;
+  uint8_t scratch_raw[4];
+  coap_rw_buffer_t scratch_buf = {scratch_raw, sizeof(scratch_raw)};
+  int rc;
+
+#ifdef COAP_DEBUG
+  NODE_DBG("Received: ");
+  coap_dump(data, len, true);
+  NODE_DBG("\n");
+#endif
+
+  if (0 != (rc = coap_parse(&pkt, data, len))){
+    NODE_DBG("Bad packet rc=%d\n", rc);
+    return 0;
+  }
+  else
+  {
+    coap_packet_t rsppkt;
+#ifdef COAP_DEBUG
+    coap_dumpPacket(&pkt);
+#endif
+    coap_handle_req(&scratch_buf, &pkt, &rsppkt);
+    if (0 != (rc = coap_build(data, &rsplen, &rsppkt))){
+      NODE_DBG("coap_build failed rc=%d\n", rc);
+      return 0;
+    }
+    else
+    {
+#ifdef COAP_DEBUG
+      NODE_DBG("Responding: ");
+      coap_dump(data, rsplen, true);
+      NODE_DBG("\n");
+#endif
+#ifdef COAP_DEBUG
+      coap_dumpPacket(&rsppkt);
+#endif
+    }
+    return rsplen;
+  }
+}
--- a/app/coap/coap_server.h
+++ b/app/coap/coap_server.h
@ -0,0 +1,14 @@
+#ifndef _COAP_SERVER_H
+#define _COAP_SERVER_H 1
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+size_t coap_server_respond(char *data, unsigned short len, unsigned short size);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
--- a/app/coap/coap_timer.c
+++ b/app/coap/coap_timer.c
@ -0,0 +1,78 @@
+#include "node.h"
+#include "coap_timer.h"
+#include "os_type.h"
+
+static os_timer_t coap_timer;
+static coap_tick_t basetime = 0;
+
+void coap_timer_elapsed(coap_tick_t *diff){
+  coap_tick_t now = system_get_time() / 1000;   // coap_tick_t is in ms. also sys_timer
+  if(now>=basetime){
+    *diff = now-basetime;
+  } else {
+    *diff = now + SYS_TIME_MAX -basetime;
+  }
+  basetime = now;
+}
+
+void coap_timer_tick(void *arg){
+  if( !arg )
+    return;
+  coap_queue_t **queue = (coap_queue_t **)arg;
+  if( !(*queue) )
+    return;
+
+  coap_queue_t *node = coap_pop_next( queue );
+  /* re-initialize timeout when maximum number of retransmissions are not reached yet */
+  if (node->retransmit_cnt < COAP_DEFAULT_MAX_RETRANSMIT) {
+    node->retransmit_cnt++;
+    node->t = node->timeout << node->retransmit_cnt;
+
+    NODE_DBG("** retransmission #%d of transaction %d\n", 
+        node->retransmit_cnt, (((uint16_t)(node->pdu->pkt->hdr.id[0]))<<8)+node->pdu->pkt->hdr.id[1]);
+    node->id = coap_send(node->pconn, node->pdu);
+    if (COAP_INVALID_TID == node->id) {
+      NODE_DBG("retransmission: error sending pdu\n");
+      coap_delete_node(node);
+    } else {
+      coap_insert_node(queue, node);    
+    }
+  } else {
+    /* And finally delete the node */
+    coap_delete_node( node );
+  }
+
+  coap_timer_start(queue);
+}
+
+void coap_timer_setup(coap_queue_t ** queue, coap_tick_t t){
+  os_timer_disarm(&coap_timer);
+  os_timer_setfn(&coap_timer, (os_timer_func_t *)coap_timer_tick, queue);
+  os_timer_arm(&coap_timer, t, 0);   // no repeat
+}
+
+void coap_timer_stop(void){
+  os_timer_disarm(&coap_timer);
+}
+
+void coap_timer_update(coap_queue_t ** queue){
+  if (!queue)
+    return;
+  coap_tick_t diff = 0;
+  coap_queue_t *first = *queue;
+  coap_timer_elapsed(&diff); // update: basetime = now, diff = now - oldbase, means time elapsed
+  if (first) {
+    // diff ms time is elapsed, re-calculate the first node->t
+    if (first->t >= diff){
+      first->t -= diff;
+    } else {
+      first->t = 0;  // when timer enabled, time out almost immediately
+    }
+  }
+}
+
+void coap_timer_start(coap_queue_t ** queue){
+  if(*queue){ // if there is node in the queue, set timeout to its ->t.
+    coap_timer_setup(queue, (*queue)->t);
+  }
+}
--- a/app/coap/coap_timer.h
+++ b/app/coap/coap_timer.h
@ -0,0 +1,31 @@
+#ifndef _COAP_TIMER_H
+#define _COAP_TIMER_H 1
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include "node.h"
+
+#define SYS_TIME_MAX (0xFFFFFFFF / 1000)
+
+#define COAP_DEFAULT_RESPONSE_TIMEOUT  2 /* response timeout in seconds */
+#define COAP_DEFAULT_MAX_RETRANSMIT    4 /* max number of retransmissions */
+#define COAP_TICKS_PER_SECOND 1000    // ms
+#define DEFAULT_MAX_TRANSMIT_WAIT   90
+
+void coap_timer_elapsed(coap_tick_t *diff);
+
+void coap_timer_setup(coap_queue_t ** queue, coap_tick_t t);
+
+void coap_timer_stop(void);
+
+void coap_timer_update(coap_queue_t ** queue);
+
+void coap_timer_start(coap_queue_t ** queue);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
--- a/app/coap/endpoints.c
+++ b/app/coap/endpoints.c
@ -0,0 +1,282 @@
+#include "c_stdio.h"
+#include "c_string.h"
+#include "coap.h"
+
+#include "lua.h"
+#include "lauxlib.h"
+#include "lualib.h"
+
+#include "os_type.h"
+
+static char rsp[MAX_PAYLOAD_SIZE] = "";
+const uint16_t rsplen = MAX_PAYLOAD_SIZE;
+void build_well_known_rsp(void);
+
+void endpoint_setup(void)
+{
+    coap_setup();
+    build_well_known_rsp();
+}
+
+static const coap_endpoint_path_t path_well_known_core = {2, {".well-known", "core"}};
+static int handle_get_well_known_core(const coap_endpoint_t *ep, coap_rw_buffer_t *scratch, const coap_packet_t *inpkt, coap_packet_t *outpkt, uint8_t id_hi, uint8_t id_lo)
+{
+    return coap_make_response(scratch, outpkt, (const uint8_t *)rsp, c_strlen(rsp), id_hi, id_lo, &inpkt->tok, COAP_RSPCODE_CONTENT, COAP_CONTENTTYPE_APPLICATION_LINKFORMAT);
+}
+
+static const coap_endpoint_path_t path_variable = {2, {"v1", "v"}};
+static int handle_get_variable(const coap_endpoint_t *ep, coap_rw_buffer_t *scratch, const coap_packet_t *inpkt, coap_packet_t *outpkt, uint8_t id_hi, uint8_t id_lo)
+{
+    const coap_option_t *opt;
+    uint8_t count;
+    if (NULL != (opt = coap_findOptions(inpkt, COAP_OPTION_URI_PATH, &count)))
+    {
+        if ((count != ep->path->count ) && (count != ep->path->count + 1)) // +1 for /f/[function], /v/[variable]
+        {
+            NODE_DBG("should never happen.\n");
+            goto end;
+        }
+        if (count == ep->path->count + 1)
+        {
+            coap_luser_entry *h = ep->user_entry->next;     // ->next: skip the first entry(head)
+            while(NULL != h){
+                if (opt[count-1].buf.len != c_strlen(h->name))
+                {
+                    h = h->next;
+                    continue;
+                }
+                if (0 == c_memcmp(h->name, opt[count-1].buf.p, opt[count-1].buf.len))
+                {
+                    NODE_DBG("/v1/v/");
+                    NODE_DBG((char *)h->name);
+                    NODE_DBG(" match.\n");
+                    if(h->L == NULL)
+                        return coap_make_response(scratch, outpkt, NULL, 0, id_hi, id_lo, &inpkt->tok, COAP_RSPCODE_NOT_FOUND, COAP_CONTENTTYPE_NONE);
+                    if(c_strlen(h->name))
+                    {
+                        lua_getglobal(h->L, h->name);
+                        if (!lua_isnumber(h->L, -1)) {
+                            NODE_DBG ("should be a number.\n");
+                            lua_pop(h->L, 1);
+                            return coap_make_response(scratch, outpkt, NULL, 0, id_hi, id_lo, &inpkt->tok, COAP_RSPCODE_NOT_FOUND, COAP_CONTENTTYPE_NONE);
+                        } else {
+                            const char *res = lua_tostring(h->L,-1);
+                            lua_pop(h->L, 1);
+                            return coap_make_response(scratch, outpkt, (const uint8_t *)res, c_strlen(res), id_hi, id_lo, &inpkt->tok, COAP_RSPCODE_CONTENT, COAP_CONTENTTYPE_TEXT_PLAIN);
+                        }
+                    }
+                } else {
+                    h = h->next;
+                }
+            }
+        }else{
+            NODE_DBG("/v1/v match.\n");
+            goto end;
+        }
+    }
+    NODE_DBG("none match.\n");
+end:
+    return coap_make_response(scratch, outpkt, NULL, 0, id_hi, id_lo, &inpkt->tok, COAP_RSPCODE_CONTENT, COAP_CONTENTTYPE_TEXT_PLAIN);
+}
+
+static const coap_endpoint_path_t path_function = {2, {"v1", "f"}};
+static int handle_post_function(const coap_endpoint_t *ep, coap_rw_buffer_t *scratch, const coap_packet_t *inpkt, coap_packet_t *outpkt, uint8_t id_hi, uint8_t id_lo)
+{
+    const coap_option_t *opt;
+    uint8_t count;
+    if (NULL != (opt = coap_findOptions(inpkt, COAP_OPTION_URI_PATH, &count)))
+    {
+        if ((count != ep->path->count ) && (count != ep->path->count + 1)) // +1 for /f/[function], /v/[variable]
+        {
+            NODE_DBG("should never happen.\n");
+            goto end;
+        }
+        if (count == ep->path->count + 1)
+        {
+            coap_luser_entry *h = ep->user_entry->next;     // ->next: skip the first entry(head)
+            while(NULL != h){
+                if (opt[count-1].buf.len != c_strlen(h->name))
+                {
+                    h = h->next;
+                    continue;
+                }
+                if (0 == c_memcmp(h->name, opt[count-1].buf.p, opt[count-1].buf.len))
+                {
+                    NODE_DBG("/v1/f/");
+                    NODE_DBG((char *)h->name);
+                    NODE_DBG(" match.\n");
+
+                    if(h->L == NULL)
+                        return coap_make_response(scratch, outpkt, NULL, 0, id_hi, id_lo, &inpkt->tok, COAP_RSPCODE_NOT_FOUND, COAP_CONTENTTYPE_NONE);
+
+                    if(c_strlen(h->name))
+                    {
+                        lua_getglobal(h->L, h->name);
+                        if (lua_type(h->L, -1) != LUA_TFUNCTION) {
+                            NODE_DBG ("should be a function\n");
+                            lua_pop(h->L, 1);
+                            return coap_make_response(scratch, outpkt, NULL, 0, id_hi, id_lo, &inpkt->tok, COAP_RSPCODE_NOT_FOUND, COAP_CONTENTTYPE_NONE);
+                        } else {
+                            lua_pushlstring(h->L, inpkt->payload.p, inpkt->payload.len);     // make sure payload.p is filled with '\0' after payload.len, or use lua_pushlstring
+                            lua_call(h->L, 1, 1);
+                            if (!lua_isnil(h->L, -1)){  /* get return? */
+                                if( lua_isstring(h->L, -1) )   // deal with the return string
+                                {
+                                    size_t len = 0;
+                                    const char *ret = luaL_checklstring( h->L, -1, &len );
+                                    if(len > MAX_PAYLOAD_SIZE){
+                                        luaL_error( h->L, "return string:<MAX_PAYLOAD_SIZE" );
+                                        return coap_make_response(scratch, outpkt, NULL, 0, id_hi, id_lo, &inpkt->tok, COAP_RSPCODE_NOT_FOUND, COAP_CONTENTTYPE_NONE);
+                                    }
+                                    NODE_DBG((char *)ret);
+                                    NODE_DBG("\n");
+                                    return coap_make_response(scratch, outpkt, ret, len, id_hi, id_lo, &inpkt->tok, COAP_RSPCODE_CONTENT, COAP_CONTENTTYPE_TEXT_PLAIN);
+                                } 
+                            } else {
+                                return coap_make_response(scratch, outpkt, NULL, 0, id_hi, id_lo, &inpkt->tok, COAP_RSPCODE_CONTENT, COAP_CONTENTTYPE_TEXT_PLAIN);
+                            }
+                        }
+                    }
+                } else {
+                    h = h->next;
+                }
+            }
+        }else{
+            NODE_DBG("/v1/f match.\n");
+            goto end;
+        }
+    }
+    NODE_DBG("none match.\n");    
+end:
+    return coap_make_response(scratch, outpkt, NULL, 0, id_hi, id_lo, &inpkt->tok, COAP_RSPCODE_NOT_FOUND, COAP_CONTENTTYPE_NONE);
+}
+
+extern lua_Load gLoad;
+extern os_timer_t lua_timer;
+extern void dojob(lua_Load *load);
+static const coap_endpoint_path_t path_command = {2, {"v1", "c"}};
+static int handle_post_command(const coap_endpoint_t *ep, coap_rw_buffer_t *scratch, const coap_packet_t *inpkt, coap_packet_t *outpkt, uint8_t id_hi, uint8_t id_lo)
+{
+    if (inpkt->payload.len == 0)
+        return coap_make_response(scratch, outpkt, NULL, 0, id_hi, id_lo, &inpkt->tok, COAP_RSPCODE_BAD_REQUEST, COAP_CONTENTTYPE_TEXT_PLAIN);
+    if (inpkt->payload.len > 0)
+    {
+        lua_Load *load = &gLoad;
+        if(load->line_position == 0){
+            coap_buffer_to_string(load->line, load->len,&inpkt->payload);
+            load->line_position = c_strlen(load->line)+1;
+            // load->line[load->line_position-1] = '\n';
+            // load->line[load->line_position] = 0;
+            // load->line_position++;
+            load->done = 1;
+            NODE_DBG("Get command:\n");
+            NODE_DBG(load->line); // buggy here
+            NODE_DBG("\nResult(if any):\n");
+            os_timer_disarm(&lua_timer);
+            os_timer_setfn(&lua_timer, (os_timer_func_t *)dojob, load);
+            os_timer_arm(&lua_timer, READLINE_INTERVAL, 0);   // no repeat
+        }
+        return coap_make_response(scratch, outpkt, NULL, 0, id_hi, id_lo, &inpkt->tok, COAP_RSPCODE_CONTENT, COAP_CONTENTTYPE_TEXT_PLAIN);
+    }
+}
+
+static uint32_t id = 0;
+static const coap_endpoint_path_t path_id = {2, {"v1", "id"}};
+static int handle_get_id(const coap_endpoint_t *ep, coap_rw_buffer_t *scratch, const coap_packet_t *inpkt, coap_packet_t *outpkt, uint8_t id_hi, uint8_t id_lo)
+{
+    id = system_get_chip_id();
+    return coap_make_response(scratch, outpkt, (const uint8_t *)(&id), sizeof(uint32_t), id_hi, id_lo, &inpkt->tok, COAP_RSPCODE_CONTENT, COAP_CONTENTTYPE_TEXT_PLAIN);
+}
+
+coap_luser_entry var_head = {NULL,NULL,NULL};
+coap_luser_entry *variable_entry = &var_head;
+
+coap_luser_entry func_head = {NULL,NULL,NULL};
+coap_luser_entry *function_entry = &func_head;
+
+const coap_endpoint_t endpoints[] =
+{
+    {COAP_METHOD_GET, handle_get_well_known_core, &path_well_known_core, "ct=40", NULL},
+    {COAP_METHOD_GET, handle_get_variable, &path_variable, "ct=0", &var_head},
+    {COAP_METHOD_POST, handle_post_function, &path_function, NULL, &func_head},
+    {COAP_METHOD_POST, handle_post_command, &path_command, NULL, NULL},
+    {COAP_METHOD_GET, handle_get_id, &path_id, "ct=0", NULL},
+    {(coap_method_t)0, NULL, NULL, NULL, NULL}
+};
+
+void build_well_known_rsp(void)
+{
+    const coap_endpoint_t *ep = endpoints;
+    int i;
+    uint16_t len = rsplen;
+
+    c_memset(rsp, 0, sizeof(rsp));
+
+    len--; // Null-terminated string
+
+    while(NULL != ep->handler)
+    {
+        if (NULL == ep->core_attr) {
+            ep++;
+            continue;
+        }
+        if (NULL == ep->user_entry){
+            if (0 < c_strlen(rsp)) {
+                c_strncat(rsp, ",", len);
+                len--;
+            }
+        
+            c_strncat(rsp, "<", len);
+            len--;
+
+            for (i = 0; i < ep->path->count; i++) {
+                c_strncat(rsp, "/", len);
+                len--;
+
+                c_strncat(rsp, ep->path->elems[i], len);
+                len -= c_strlen(ep->path->elems[i]);
+            }
+
+            c_strncat(rsp, ">;", len);
+            len -= 2;
+
+            c_strncat(rsp, ep->core_attr, len);
+            len -= c_strlen(ep->core_attr);
+        } else {
+            coap_luser_entry *h = ep->user_entry->next;     // ->next: skip the first entry(head)
+            while(NULL != h){
+                if (0 < c_strlen(rsp)) {
+                    c_strncat(rsp, ",", len);
+                    len--;
+                }
+            
+                c_strncat(rsp, "<", len);
+                len--;
+
+                for (i = 0; i < ep->path->count; i++) {
+                    c_strncat(rsp, "/", len);
+                    len--;
+
+                    c_strncat(rsp, ep->path->elems[i], len);
+                    len -= c_strlen(ep->path->elems[i]);
+                }
+
+                c_strncat(rsp, "/", len);
+                len--;
+
+                c_strncat(rsp, h->name, len);
+                len -= c_strlen(h->name);
+
+                c_strncat(rsp, ">;", len);
+                len -= 2;
+
+                c_strncat(rsp, ep->core_attr, len);
+                len -= c_strlen(ep->core_attr);  
+
+                h = h->next;
+            }
+        }
+        ep++;
+    }
+}
+
--- a/app/coap/hash.c
+++ b/app/coap/hash.c
@ -0,0 +1,30 @@
+#include "hash.h"
+#include "c_string.h"
+/* Caution: When changing this, update COAP_DEFAULT_WKC_HASHKEY
+ * accordingly (see int coap_hash_path());
+ */
+void coap_hash(const unsigned char *s, unsigned int len, coap_key_t h) {
+  size_t j;
+
+  while (len--) {
+    j = sizeof(coap_key_t)-1;
+  
+    while (j) {
+      h[j] = ((h[j] << 7) | (h[j-1] >> 1)) + h[j];
+      --j;
+    }
+
+    h[0] = (h[0] << 7) + h[0] + *s++;
+  }
+}
+
+void coap_transaction_id(const uint32_t ip, const uint32_t port, const coap_packet_t *pkt, coap_tid_t *id) {
+  coap_key_t h;
+  c_memset(h, 0, sizeof(coap_key_t));
+
+  /* Compare the transport address. */
+  coap_hash((const unsigned char *)&(port), sizeof(port), h); 
+  coap_hash((const unsigned char *)&(ip), sizeof(ip), h); 
+  coap_hash((const unsigned char *)(pkt->hdr.id), sizeof(pkt->hdr.id), h);
+  *id = ((h[0] << 8) | h[1]) ^ ((h[2] << 8) | h[3]);
+}
--- a/app/coap/hash.h
+++ b/app/coap/hash.h
@ -0,0 +1,23 @@
+#ifndef _HASH_H
+#define _HASH_H 1
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include "coap.h"
+
+typedef unsigned char coap_key_t[4];
+
+/* CoAP transaction id */
+/*typedef unsigned short coap_tid_t; */
+typedef int coap_tid_t;
+#define COAP_INVALID_TID -1
+
+void coap_transaction_id(const uint32_t ip, const uint32_t port, const coap_packet_t *pkt, coap_tid_t *id);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
--- a/app/coap/node.c
+++ b/app/coap/node.c
@ -0,0 +1,141 @@
+#include "c_string.h"
+#include "c_stdlib.h"
+#include "node.h"
+
+static inline coap_queue_t *
+coap_malloc_node(void) {
+  return (coap_queue_t *)c_zalloc(sizeof(coap_queue_t));
+}
+
+void coap_free_node(coap_queue_t *node) {
+  c_free(node);
+}
+
+int coap_insert_node(coap_queue_t **queue, coap_queue_t *node) {
+  coap_queue_t *p, *q;
+  if ( !queue || !node )
+    return 0;
+
+  /* set queue head if empty */
+  if ( !*queue ) {
+    *queue = node;
+    return 1;
+  }
+
+  /* replace queue head if PDU's time is less than head's time */
+  q = *queue;
+  if (node->t < q->t) {
+    node->next = q;
+    *queue = node;
+    q->t -= node->t;		/* make q->t relative to node->t */
+    return 1;
+  }
+
+  /* search for right place to insert */
+  do {
+    node->t -= q->t;		/* make node-> relative to q->t */
+    p = q;
+    q = q->next;
+  } while (q && q->t <= node->t);
+
+  /* insert new item */
+  if (q) {
+    q->t -= node->t;		/* make q->t relative to node->t */
+  }
+  node->next = q;
+  p->next = node;
+  return 1;
+}
+
+int coap_delete_node(coap_queue_t *node) {
+  if ( !node )
+    return 0;
+
+  coap_delete_pdu(node->pdu);
+  coap_free_node(node);
+
+  return 1;
+}
+
+void coap_delete_all(coap_queue_t *queue) {
+  if ( !queue )
+    return;
+
+  coap_delete_all( queue->next );
+  coap_delete_node( queue );
+}
+
+coap_queue_t * coap_new_node(void) {
+  coap_queue_t *node;
+  node = coap_malloc_node();
+
+  if ( ! node ) {
+    return NULL;
+  }
+
+  c_memset(node, 0, sizeof(*node));
+  return node;
+}
+
+coap_queue_t * coap_peek_next( coap_queue_t *queue ) {
+  if ( !queue )
+    return NULL;
+
+  return queue;
+}
+
+coap_queue_t * coap_pop_next( coap_queue_t **queue ) {		// this function is called inside timeout callback only.
+  coap_queue_t *next;
+
+  if ( !(*queue) )
+    return NULL;
+
+  next = *queue;
+  *queue = (*queue)->next;
+  // if (queue) {
+  //   queue->t += next->t;
+  // }
+  next->next = NULL;
+  return next;
+}
+
+int coap_remove_node( coap_queue_t **queue, const coap_tid_t id){
+  coap_queue_t *p, *q, *node;
+  if ( !queue ) 
+    return 0;
+  if ( !*queue )  // if empty
+    return 0;
+
+  q = *queue;
+  if (q->id == id) {
+    node = q;
+    *queue = q->next;
+    node->next = NULL;
+    if(*queue){
+      (*queue)->t += node->t;
+    }
+    coap_delete_node(node);
+    return 1;
+  }
+
+  /* search for right node to remove */
+  while (q && q->id != id) {
+    p = q;
+    q = q->next;
+  }
+
+  /* find the node */
+  if (q) {
+    node = q; /* save the node */
+    p->next = q->next;  /* remove the node */
+    q = q->next;
+    node->next = NULL;
+    if (q)   // add node->t to the node after.
+    {
+      q->t += node->t;
+    }
+    coap_delete_node(node);
+    return 1;
+  }
+  return 0;
+}
--- a/app/coap/node.h
+++ b/app/coap/node.h
@ -0,0 +1,58 @@
+#ifndef _NODE_H
+#define _NODE_H 1
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include "hash.h"
+#include "pdu.h"
+
+struct coap_queue_t;
+typedef uint32_t coap_tick_t;
+
+/*
+1. queue(first)->t store when to send PDU for the next time, it's a base(absolute) time
+2. queue->next->t store the delta between time and base-time.  queue->next->t = timeout + now - basetime
+3. node->next->t store the delta between time and previous->t.  node->next->t = timeout + now - node->t - basetime
+4. time to fire:   10,   15,    18,    25
+		node->t:   10,   5,     3,     7
+*/
+
+typedef struct coap_queue_t {
+  struct coap_queue_t *next;
+
+  coap_tick_t t;	        /**< when to send PDU for the next time */
+  unsigned char retransmit_cnt;	/**< retransmission counter, will be removed when zero */
+  unsigned int timeout;		/**< the randomized timeout value */
+
+  coap_tid_t id;		/**< unique transaction id */
+
+  // coap_packet_t *pkt;
+  coap_pdu_t *pdu;		/**< the CoAP PDU to send */
+  struct espconn *pconn;
+} coap_queue_t;
+
+void coap_free_node(coap_queue_t *node);
+
+/** Adds node to given queue, ordered by node->t. */
+int coap_insert_node(coap_queue_t **queue, coap_queue_t *node);
+
+/** Destroys specified node. */
+int coap_delete_node(coap_queue_t *node);
+
+/** Removes all items from given queue and frees the allocated storage. */
+void coap_delete_all(coap_queue_t *queue);
+
+/** Creates a new node suitable for adding to the CoAP sendqueue. */
+coap_queue_t *coap_new_node(void);
+
+coap_queue_t *coap_pop_next( coap_queue_t **queue );
+
+int coap_remove_node( coap_queue_t **queue, const coap_tid_t id);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
--- a/app/coap/pdu.c
+++ b/app/coap/pdu.c
@ -0,0 +1,63 @@
+#include "c_stdlib.h"
+#include "pdu.h"
+
+coap_pdu_t * coap_new_pdu(void) {
+  coap_pdu_t *pdu = NULL;
+  pdu = (coap_pdu_t *)c_zalloc(sizeof(coap_pdu_t));
+  if(!pdu){
+    NODE_DBG("coap_new_pdu malloc error.\n");
+    return NULL;
+  }
+
+  pdu->scratch.p = (uint8_t *)c_zalloc(MAX_REQ_SCRATCH_SIZE);
+  if(!pdu->scratch.p){
+    NODE_DBG("coap_new_pdu malloc error.\n");
+    c_free(pdu);
+    return NULL;
+  }
+  pdu->scratch.len = MAX_REQ_SCRATCH_SIZE;
+  
+  pdu->pkt = (coap_packet_t *)c_zalloc(sizeof(coap_packet_t));
+  if(!pdu->pkt){
+    NODE_DBG("coap_new_pdu malloc error.\n");
+    c_free(pdu->scratch.p);
+    c_free(pdu);
+    return NULL;
+  }
+
+  pdu->msg.p = (uint8_t *)c_zalloc(MAX_REQUEST_SIZE+1); // +1 for string '\0'
+  if(!pdu->msg.p){
+    NODE_DBG("coap_new_pdu malloc error.\n");
+    c_free(pdu->pkt);
+    c_free(pdu->scratch.p);
+    c_free(pdu);
+    return NULL;
+  }
+  pdu->msg.len = MAX_REQUEST_SIZE;
+  return pdu;
+}
+
+void coap_delete_pdu(coap_pdu_t *pdu){
+  if(!pdu)
+    return;
+
+  if(pdu->scratch.p){
+    c_free(pdu->scratch.p);
+    pdu->scratch.p = NULL;
+    pdu->scratch.len = 0;
+  }
+
+  if(pdu->pkt){
+    c_free(pdu->pkt);
+    pdu->pkt = NULL;
+  }
+
+  if(pdu->msg.p){
+    c_free(pdu->msg.p);
+    pdu->msg.p = NULL;
+    pdu->msg.len = 0;
+  }
+
+  c_free(pdu);
+  pdu = NULL;
+}
--- a/app/coap/pdu.h
+++ b/app/coap/pdu.h
@ -0,0 +1,25 @@
+#ifndef _PDU_H
+#define _PDU_H 1
+
+#ifdef __cplusplus
+extern "C" {
+#endif
+
+#include "coap.h"
+
+/** Header structure for CoAP PDUs */
+typedef struct {
+  coap_rw_buffer_t scratch;
+  coap_packet_t *pkt;
+  coap_rw_buffer_t msg;   /**< the CoAP msg to send */
+} coap_pdu_t;
+
+coap_pdu_t *coap_new_pdu(void);
+
+void coap_delete_pdu(coap_pdu_t *pdu);
+
+#ifdef __cplusplus
+}
+#endif
+
+#endif
--- a/app/coap/str.c
+++ b/app/coap/str.c
@ -0,0 +1,28 @@
+/* str.c -- strings to be used in the CoAP library
+ *
+ * Copyright (C) 2010,2011 Olaf Bergmann <bergmann@tzi.org>
+ *
+ * This file is part of the CoAP library libcoap. Please see
+ * README for terms of use. 
+ */
+
+#include "c_stdlib.h"
+#include "c_types.h"
+ 
+#include "str.h"
+
+str * coap_new_string(size_t size) {
+  str *s = (str *)c_malloc(sizeof(str) + size + 1);
+  if ( !s ) {
+    return NULL;
+  }
+
+  c_memset(s, 0, sizeof(str));
+  s->s = ((unsigned char *)s) + sizeof(str);
+  return s;
+}
+
+void coap_delete_string(str *s) {
+  c_free(s);
+}
+
--- a/app/coap/str.h
+++ b/app/coap/str.h
@ -0,0 +1,30 @@
+/* str.h -- strings to be used in the CoAP library
+ *
+ * Copyright (C) 2010,2011 Olaf Bergmann <bergmann@tzi.org>
+ *
+ * This file is part of the CoAP library libcoap. Please see
+ * README for terms of use. 
+ */
+
+#ifndef _COAP_STR_H_
+#define _COAP_STR_H_
+
+#include "c_string.h"
+
+typedef struct {
+  size_t length;		/* length of string */
+  unsigned char *s;		/* string data */
+} str;
+
+#define COAP_SET_STR(st,l,v) { (st)->length = (l), (st)->s = (v); }
+
+/**
+ * Returns a new string object with at least size bytes storage
+ * allocated.  The string must be released using coap_delete_string();
+ */
+str *coap_new_string(size_t size);
+
+/** Deletes the given string and releases any memory allocated. */
+void coap_delete_string(str *);
+
+#endif /* _COAP_STR_H_ */
--- a/app/coap/uri.c
+++ b/app/coap/uri.c
@ -0,0 +1,468 @@
+/* uri.c -- helper functions for URI treatment
+ */
+
+#include "c_stdio.h"
+#include "c_stdlib.h"
+#include "c_string.h"
+#include "c_ctype.h"
+
+#include "coap.h"
+#include "uri.h"
+
+#ifndef assert
+// #warning "assertions are disabled"
+#  define assert(x) do { \
+        if(!x) NODE_ERR("uri.c assert!\n");  \
+    } while (0)
+#endif
+
+
+/** 
+ * A length-safe version of strchr(). This function returns a pointer
+ * to the first occurrence of @p c  in @p s, or @c NULL if not found.
+ * 
+ * @param s   The string to search for @p c.
+ * @param len The length of @p s.
+ * @param c   The character to search.
+ * 
+ * @return A pointer to the first occurence of @p c, or @c NULL 
+ * if not found.
+ */
+static inline unsigned char *
+strnchr(unsigned char *s, size_t len, unsigned char c) {
+  while (len && *s++ != c)
+    --len;
+  
+  return len ? s : NULL;
+}
+
+int coap_split_uri(unsigned char *str_var, size_t len, coap_uri_t *uri) {
+  unsigned char *p, *q;
+  int secure = 0, res = 0;
+
+  if (!str_var || !uri)
+    return -1;
+
+  c_memset(uri, 0, sizeof(coap_uri_t));
+  uri->port = COAP_DEFAULT_PORT;
+
+  /* search for scheme */
+  p = str_var;
+  if (*p == '/') {
+    q = p;
+    goto path;
+  }
+
+  q = (unsigned char *)COAP_DEFAULT_SCHEME;
+  while (len && *q && tolower(*p) == *q) {
+    ++p; ++q; --len;
+  }
+  
+  /* If q does not point to the string end marker '\0', the schema
+   * identifier is wrong. */
+  if (*q) {
+    res = -1;
+    goto error;
+  }
+
+  /* There might be an additional 's', indicating the secure version: */
+  if (len && (secure = tolower(*p) == 's')) {
+    ++p; --len;
+  }
+
+  q = (unsigned char *)"://";
+  while (len && *q && tolower(*p) == *q) {
+    ++p; ++q; --len;
+  }
+
+  if (*q) {
+    res = -2;
+    goto error;
+  }
+
+  /* p points to beginning of Uri-Host */
+  q = p;
+  if (len && *p == '[') {	/* IPv6 address reference */
+    ++p;
+    
+    while (len && *q != ']') {
+      ++q; --len;
+    }
+
+    if (!len || *q != ']' || p == q) {
+      res = -3;
+      goto error;
+    } 
+
+    COAP_SET_STR(&uri->host, q - p, p);
+    ++q; --len;
+  } else {			/* IPv4 address or FQDN */
+    while (len && *q != ':' && *q != '/' && *q != '?') {
+      *q = tolower(*q);
+      ++q;
+      --len;
+    }
+
+    if (p == q) {
+      res = -3;
+      goto error;
+    }
+
+    COAP_SET_STR(&uri->host, q - p, p);
+  }
+
+  /* check for Uri-Port */
+  if (len && *q == ':') {
+    p = ++q;
+    --len;
+    
+    while (len && isdigit(*q)) {
+      ++q;
+      --len;
+    }
+
+    if (p < q) {		/* explicit port number given */
+      int uri_port = 0;
+    
+      while (p < q)
+	     uri_port = uri_port * 10 + (*p++ - '0');
+
+      uri->port = uri_port;
+    } 
+  }
+  
+ path:		 /* at this point, p must point to an absolute path */
+
+  if (!len)
+    goto end;
+  
+  if (*q == '/') {
+    p = ++q;
+    --len;
+
+    while (len && *q != '?') {
+      ++q;
+      --len;
+    }
+  
+    if (p < q) {
+      COAP_SET_STR(&uri->path, q - p, p);
+      p = q;
+    }
+  }
+
+  /* Uri_Query */
+  if (len && *p == '?') {
+    ++p;
+    --len;
+    COAP_SET_STR(&uri->query, len, p);
+    len = 0;
+  }
+
+  end:
+  return len ? -1 : 0;
+  
+  error:
+  return res;
+}
+
+/** 
+ * Calculates decimal value from hexadecimal ASCII character given in
+ * @p c. The caller must ensure that @p c actually represents a valid
+ * heaxdecimal character, e.g. with isxdigit(3). 
+ *
+ * @hideinitializer
+ */
+#define hexchar_to_dec(c) ((c) & 0x40 ? ((c) & 0x0F) + 9 : ((c) & 0x0F))
+
+/** 
+ * Decodes percent-encoded characters while copying the string @p seg
+ * of size @p length to @p buf. The caller of this function must
+ * ensure that the percent-encodings are correct (i.e. the character
+ * '%' is always followed by two hex digits. and that @p buf provides
+ * sufficient space to hold the result. This function is supposed to
+ * be called by make_decoded_option() only.
+ * 
+ * @param seg     The segment to decode and copy.
+ * @param length  Length of @p seg.
+ * @param buf     The result buffer.
+ */
+void decode_segment(const unsigned char *seg, size_t length, unsigned char *buf) {
+
+  while (length--) {
+
+    if (*seg == '%') {
+      *buf = (hexchar_to_dec(seg[1]) << 4) + hexchar_to_dec(seg[2]);
+      
+      seg += 2; length -= 2;
+    } else {
+      *buf = *seg;
+    }
+    
+    ++buf; ++seg;
+  }
+}
+
+/**
+ * Runs through the given path (or query) segment and checks if
+ * percent-encodings are correct. This function returns @c -1 on error
+ * or the length of @p s when decoded.
+ */
+int check_segment(const unsigned char *s, size_t length) {
+
+  size_t n = 0;
+
+  while (length) {
+    if (*s == '%') {
+      if (length < 2 || !(isxdigit(s[1]) && isxdigit(s[2])))
+        return -1;
+      
+      s += 2;
+      length -= 2;
+    }
+
+    ++s; ++n; --length;
+  }
+  
+  return n;
+}
+	 
+/** 
+ * Writes a coap option from given string @p s to @p buf. @p s should
+ * point to a (percent-encoded) path or query segment of a coap_uri_t
+ * object.  The created option will have type @c 0, and the length
+ * parameter will be set according to the size of the decoded string.
+ * On success, this function returns the option's size, or a value
+ * less than zero on error. This function must be called from
+ * coap_split_path_impl() only.
+ * 
+ * @param s       The string to decode.
+ * @param length  The size of the percent-encoded string @p s.
+ * @param buf     The buffer to store the new coap option.
+ * @param buflen  The maximum size of @p buf.
+ * 
+ * @return The option's size, or @c -1 on error.
+ *
+ * @bug This function does not split segments that are bigger than 270
+ * bytes.
+ */
+int make_decoded_option(const unsigned char *s, size_t length, 
+		    unsigned char *buf, size_t buflen) {
+  int res;
+  size_t written;
+
+  if (!buflen) {
+    NODE_DBG("make_decoded_option(): buflen is 0!\n");
+    return -1;
+  }
+
+  res = check_segment(s, length);
+  if (res < 0)
+    return -1;
+
+  /* write option header using delta 0 and length res */
+  // written = coap_opt_setheader(buf, buflen, 0, res);
+  written = coap_buildOptionHeader(0, res, buf, buflen);
+
+  assert(written <= buflen);
+
+  if (!written)			/* encoding error */
+    return -1;
+
+  buf += written;		/* advance past option type/length */
+  buflen -= written;
+
+  if (buflen < (size_t)res) {
+    NODE_DBG("buffer too small for option\n");
+    return -1;
+  }
+
+  decode_segment(s, length, buf);
+
+  return written + res;
+}
+
+
+#ifndef min
+#define min(a,b) ((a) < (b) ? (a) : (b))
+#endif
+
+typedef void (*segment_handler_t)(unsigned char *, size_t, void *);
+
+/** 
+ * Splits the given string into segments. You should call one of the
+ * macros coap_split_path() or coap_split_query() instead.
+ * 
+ * @param parse_iter The iterator used for tokenizing.
+ * @param h      A handler that is called with every token.
+ * @param data   Opaque data that is passed to @p h when called.
+ * 
+ * @return The number of characters that have been parsed from @p s.
+ */
+size_t coap_split_path_impl(coap_parse_iterator_t *parse_iter,
+		     segment_handler_t h, void *data) {
+  unsigned char *seg;
+  size_t length;
+  
+  assert(parse_iter);
+  assert(h);
+
+  length = parse_iter->n;
+  
+  while ( (seg = coap_parse_next(parse_iter)) ) {
+
+    /* any valid path segment is handled here: */
+    h(seg, parse_iter->segment_length, data);
+  }
+  
+  return length - (parse_iter->n - parse_iter->segment_length);
+}
+
+struct pkt_scr {
+  coap_packet_t *pkt;
+  coap_rw_buffer_t *scratch;
+  int n;
+};
+
+void write_option(unsigned char *s, size_t len, void *data) {
+  struct pkt_scr *state = (struct pkt_scr *)data;
+  int res;
+  assert(state);
+
+  /* skip empty segments and those that consist of only one or two dots */
+  if (memcmp(s, "..", min(len,2)) == 0)
+    return;
+  
+  res = check_segment(s, len);
+  if (res < 0){
+    NODE_DBG("not a valid segment\n");
+    return;
+  }
+
+  if (state->scratch->len < (size_t)res) {
+    NODE_DBG("buffer too small for option\n");
+    return;
+  }
+
+  decode_segment(s, len, state->scratch->p);
+
+  if (res > 0) {
+    state->pkt->opts[state->pkt->numopts].buf.p = state->scratch->p;
+    state->pkt->opts[state->pkt->numopts].buf.len = res;
+    state->scratch->p += res;
+    state->scratch->len -= res;
+    state->pkt->numopts++;
+    state->n++;
+  }
+}
+
+int coap_split_path(coap_rw_buffer_t *scratch, coap_packet_t *pkt, const unsigned char *s, size_t length) {
+  struct pkt_scr tmp = { pkt, scratch, 0 };
+  coap_parse_iterator_t pi;
+
+  coap_parse_iterator_init((unsigned char *)s, length, 
+         '/', (unsigned char *)"?#", 2, &pi);
+  coap_split_path_impl(&pi, write_option, &tmp);
+
+  int i;
+  for(i=0;i<tmp.n;i++){
+    pkt->opts[pkt->numopts - i - 1].num = COAP_OPTION_URI_PATH;
+  }
+
+  return tmp.n;
+}
+
+int coap_split_query(coap_rw_buffer_t *scratch, coap_packet_t *pkt, const unsigned char *s, size_t length) {
+  struct pkt_scr tmp = { pkt, scratch, 0 };
+  coap_parse_iterator_t pi;
+
+  coap_parse_iterator_init((unsigned char *)s, length, 
+         '&', (unsigned char *)"#", 1, &pi);
+
+  coap_split_path_impl(&pi, write_option, &tmp);
+
+  int i;
+  for(i=0;i<tmp.n;i++){
+    pkt->opts[pkt->numopts - i - 1].num = COAP_OPTION_URI_QUERY;
+  }
+
+  return tmp.n;
+}
+
+#define URI_DATA(uriobj) ((unsigned char *)(uriobj) + sizeof(coap_uri_t))
+
+coap_uri_t * coap_new_uri(const unsigned char *uri, unsigned int length) {
+  unsigned char *result;
+
+  result = (unsigned char *)c_malloc(length + 1 + sizeof(coap_uri_t));
+
+  if (!result)
+    return NULL;
+
+  c_memcpy(URI_DATA(result), uri, length);
+  URI_DATA(result)[length] = '\0'; /* make it zero-terminated */
+
+  if (coap_split_uri(URI_DATA(result), length, (coap_uri_t *)result) < 0) {
+    c_free(result);
+    return NULL;
+  }
+  return (coap_uri_t *)result;
+}
+
+/* iterator functions */
+
+coap_parse_iterator_t * coap_parse_iterator_init(unsigned char *s, size_t n, 
+			 unsigned char separator,
+			 unsigned char *delim, size_t dlen,
+			 coap_parse_iterator_t *pi) {
+  assert(pi);
+  assert(separator);
+
+  pi->separator = separator;
+  pi->delim = delim;
+  pi->dlen = dlen;
+  pi->pos = s;
+  pi->n = n;
+  pi->segment_length = 0;
+
+  return pi;
+}
+
+unsigned char * coap_parse_next(coap_parse_iterator_t *pi) {
+  unsigned char *p;
+
+  if (!pi)
+    return NULL;
+
+  /* proceed to the next segment */
+  pi->n -= pi->segment_length;
+  pi->pos += pi->segment_length;
+  pi->segment_length = 0;
+
+  /* last segment? */
+  if (!pi->n || strnchr(pi->delim, pi->dlen, *pi->pos)) {
+    pi->pos = NULL;
+    return NULL;
+  }
+
+  /* skip following separator (the first segment might not have one) */
+  if (*pi->pos == pi->separator) {
+    ++pi->pos;
+    --pi->n;
+  }
+
+  p = pi->pos;
+
+  while (pi->segment_length < pi->n && *p != pi->separator &&
+	 !strnchr(pi->delim, pi->dlen, *p)) {
+    ++p;
+    ++pi->segment_length;
+  }
+
+  if (!pi->n) {
+    pi->pos = NULL;
+    pi->segment_length = 0;
+  }
+
+  return pi->pos;
+}
--- a/app/coap/uri.h
+++ b/app/coap/uri.h
@ -0,0 +1,166 @@
+/* uri.h -- helper functions for URI treatment
+ *
+ * Copyright (C) 2010,2011 Olaf Bergmann <bergmann@tzi.org>
+ *
+ * This file is part of the CoAP library libcoap. Please see
+ * README for terms of use. 
+ */
+
+#ifndef _COAP_URI_H_
+#define _COAP_URI_H_
+
+#define COAP_DEFAULT_SCHEME        "coap" /* the default scheme for CoAP URIs */
+#define COAP_DEFAULT_PORT   5683
+
+#include "str.h"
+
+/** Representation of parsed URI. Components may be filled from a
+ * string with coap_split_uri() and can be used as input for
+ * option-creation functions. */
+typedef struct {
+  str host;			/**< host part of the URI */
+  unsigned short port;		/**< The port in host byte order */
+  str path;			/**< Beginning of the first path segment. 
+				   Use coap_split_path() to create Uri-Path options */
+  str query;			/**<  The query part if present */
+} coap_uri_t;
+
+/**
+ * Creates a new coap_uri_t object from the specified URI. Returns the new
+ * object or NULL on error. The memory allocated by the new coap_uri_t
+ * must be released using coap_free().
+ * @param uri The URI path to copy.
+ * @para length The length of uri.
+ *
+ * @return New URI object or NULL on error.
+ */
+coap_uri_t *coap_new_uri(const unsigned char *uri, unsigned int length);
+
+/**
+ * @defgroup uri_parse URI Parsing Functions
+ *
+ * CoAP PDUs contain normalized URIs with their path and query split into
+ * multiple segments. The functions in this module help splitting strings.
+ * @{
+ */
+
+/** 
+ * Iterator to for tokenizing a URI path or query. This structure must
+ * be initialized with coap_parse_iterator_init(). Call
+ * coap_parse_next() to walk through the tokens.
+ *
+ * @code
+ * unsigned char *token;
+ * coap_parse_iterator_t pi;
+ * coap_parse_iterator_init(uri.path.s, uri.path.length, '/', "?#", 2, &pi);
+ *
+ * while ((token = coap_parse_next(&pi))) {
+ *   ... do something with token ...
+ * }
+ * @endcode
+ */
+typedef struct {
+  size_t n;			/**< number of remaining characters in buffer */
+  unsigned char separator;	/**< segment separators */
+  unsigned char *delim; 	/**< delimiters where to split the string */
+  size_t dlen;			/**< length of separator */
+  unsigned char *pos;		/**< current position in buffer */
+  size_t segment_length;	/**< length of current segment */
+} coap_parse_iterator_t;
+
+/** 
+ * Initializes the given iterator @p pi. 
+ * 
+ * @param s         The string to tokenize.
+ * @param n         The length of @p s.
+ * @param separator The separator character that delimits tokens.
+ * @param delim     A set of characters that delimit @s.
+ * @param dlen      The length of @p delim.
+ * @param pi        The iterator object to initialize.
+ * 
+ * @return The initialized iterator object @p pi.
+ */
+coap_parse_iterator_t *
+coap_parse_iterator_init(unsigned char *s, size_t n, 
+			 unsigned char separator,
+			 unsigned char *delim, size_t dlen,
+			 coap_parse_iterator_t *pi);
+
+/** 
+ * Updates the iterator @p pi to point to the next token. This
+ * function returns a pointer to that token or @c NULL if no more
+ * tokens exist. The contents of @p pi will be updated. In particular,
+ * @c pi->segment_length specifies the length of the current token, @c
+ * pi->pos points to its beginning.
+ * 
+ * @param pi The iterator to update.
+ * 
+ * @return The next token or @c NULL if no more tokens exist.
+ */
+unsigned char *coap_parse_next(coap_parse_iterator_t *pi);
+
+/** 
+ * Parses a given string into URI components. The identified syntactic
+ * components are stored in the result parameter @p uri. Optional URI
+ * components that are not specified will be set to { 0, 0 }, except
+ * for the port which is set to @c COAP_DEFAULT_PORT. This function
+ * returns @p 0 if parsing succeeded, a value less than zero
+ * otherwise.
+ * 
+ * @param str_var The string to split up.
+ * @param len     The actual length of @p str_var
+ * @param uri     The coap_uri_t object to store the result.
+ * @return @c 0 on success, or < 0 on error.
+ *
+ * @note The host name part will be converted to lower case by this
+ * function.
+ */
+int
+coap_split_uri(unsigned char *str_var, size_t len, coap_uri_t *uri);
+
+/** 
+ * Splits the given URI path into segments. Each segment is preceded
+ * by an option pseudo-header with delta-value 0 and the actual length
+ * of the respective segment after percent-decoding.
+ * 
+ * @param s      The path string to split. 
+ * @param length The actual length of @p s.
+ * @param buf    Result buffer for parsed segments. 
+ * @param buflen Maximum length of @p buf. Will be set to the actual number
+ * of bytes written into buf on success.
+ * 
+ * @return The number of segments created or @c -1 on error.
+ */
+#if 0
+int coap_split_path(const unsigned char *s, size_t length, 
+		    unsigned char *buf, size_t *buflen);
+#else
+int
+coap_split_path(coap_rw_buffer_t *scratch, coap_packet_t *pkt, 
+        const unsigned char *s, size_t length);
+#endif
+/** 
+ * Splits the given URI query into segments. Each segment is preceded
+ * by an option pseudo-header with delta-value 0 and the actual length
+ * of the respective query term.
+ * 
+ * @param s      The query string to split. 
+ * @param length The actual length of @p s.
+ * @param buf    Result buffer for parsed segments. 
+ * @param buflen Maximum length of @p buf. Will be set to the actual number
+ * of bytes written into buf on success.
+ * 
+ * @return The number of segments created or @c -1 on error.
+ *
+ * @bug This function does not reserve additional space for delta > 12.
+ */
+#if 0
+int coap_split_query(const unsigned char *s, size_t length, 
+		     unsigned char *buf, size_t *buflen);
+#else 
+int coap_split_query(coap_rw_buffer_t *scratch, coap_packet_t *pkt, 
+          const unsigned char *s, size_t length);
+#endif
+/** @} */
+
+#endif /* _COAP_URI_H_ */
--- a/app/include/user_config.h
+++ b/app/include/user_config.h
@ -1,14 +1,6 @@
 #ifndef __USER_CONFIG_H__
 #define __USER_CONFIG_H__

-#define NODE_VERSION_MAJOR		0U
-#define NODE_VERSION_MINOR		9U
-#define NODE_VERSION_REVISION	5U
-#define NODE_VERSION_INTERNAL   0U
-
-#define NODE_VERSION	"NodeMCU 0.9.5"
-#define BUILD_DATE	    "build 20150214"
-
 // #define DEVKIT_VERSION_0_9 1 	// define this only if you use NodeMCU devkit v0.9

 // #define FLASH_512K
@ -25,6 +17,7 @@

 #ifdef DEVELOP_VERSION
 #define NODE_DEBUG
+#define COAP_DEBUG
 #endif	/* DEVELOP_VERSION */

 #define NODE_ERROR
@ -51,33 +44,6 @@
 // #define BUILD_WOFS		1
 #define BUILD_SPIFFS	1

-#define LUA_USE_MODULES
-
-#ifdef LUA_USE_MODULES
-#define LUA_USE_MODULES_NODE
-#define LUA_USE_MODULES_FILE
-#define LUA_USE_MODULES_GPIO
-#define LUA_USE_MODULES_WIFI
-#define LUA_USE_MODULES_NET
-#define LUA_USE_MODULES_PWM
-#define LUA_USE_MODULES_I2C
-#define LUA_USE_MODULES_SPI
-#define LUA_USE_MODULES_TMR
-#define LUA_USE_MODULES_ADC
-#define LUA_USE_MODULES_UART
-#define LUA_USE_MODULES_OW
-#define LUA_USE_MODULES_BIT
-#define LUA_USE_MODULES_U8G
-#define LUA_USE_MODULES_MQTT
-#define LUA_USE_MODULES_WS2812	// TODO: put this device specific module to device driver section.
-#endif /* LUA_USE_MODULES */
-
-// TODO: put device specific module to device driver section.
-#ifdef LUA_USE_DEVICE_DRIVER
-#define LUA_USE_DEVICE_WS2812
-#endif /* LUA_USE_DEVICE_DRIVER */
-
-
 // #define LUA_NUMBER_INTEGRAL

 #define LUA_OPTRAM
@ -99,7 +65,6 @@
 #define LED_LOW_COUNT_DEFAULT 0
 #endif

-
 // Configure U8glib fonts
 // add a U8G_FONT_TABLE_ENTRY for each font you want to compile into the image
 #define U8G_FONT_TABLE_ENTRY(font)
--- a/app/include/user_modules.h
+++ b/app/include/user_modules.h
@ -0,0 +1,35 @@
+#ifndef __USER_MODULES_H__
+#define __USER_MODULES_H__
+
+#define LUA_USE_BUILTIN_STRING		// for string.xxx()
+#define LUA_USE_BUILTIN_TABLE		// for table.xxx()
+#define LUA_USE_BUILTIN_COROUTINE	// for coroutine.xxx()
+#define LUA_USE_BUILTIN_MATH		// for math.xxx(), partially work
+// #define LUA_USE_BUILTIN_IO 			// for io.xxx(), partially work
+
+// #define LUA_USE_BUILTIN_OS			// for os.xxx(), not work
+// #define LUA_USE_BUILTIN_DEBUG		// for debug.xxx(), not work
+
+#define LUA_USE_MODULES
+
+#ifdef LUA_USE_MODULES
+#define LUA_USE_MODULES_NODE
+#define LUA_USE_MODULES_FILE
+#define LUA_USE_MODULES_GPIO
+#define LUA_USE_MODULES_WIFI
+#define LUA_USE_MODULES_NET
+#define LUA_USE_MODULES_PWM
+#define LUA_USE_MODULES_I2C
+#define LUA_USE_MODULES_SPI
+#define LUA_USE_MODULES_TMR
+#define LUA_USE_MODULES_ADC
+#define LUA_USE_MODULES_UART
+#define LUA_USE_MODULES_OW
+#define LUA_USE_MODULES_BIT
+#define LUA_USE_MODULES_MQTT
+// #define LUA_USE_MODULES_COAP			// need about 4k more ram for now
+#define LUA_USE_MODULES_U8G
+#define LUA_USE_MODULES_WS2812
+#endif /* LUA_USE_MODULES */
+
+#endif	/* __USER_MODULES_H__ */
--- a/app/include/user_version.h
+++ b/app/include/user_version.h
@ -0,0 +1,12 @@
+#ifndef __USER_VERSION_H__
+#define __USER_VERSION_H__
+
+#define NODE_VERSION_MAJOR		0U
+#define NODE_VERSION_MINOR		9U
+#define NODE_VERSION_REVISION	5U
+#define NODE_VERSION_INTERNAL   0U
+
+#define NODE_VERSION	"NodeMCU 0.9.5"
+#define BUILD_DATE	    "build 20150306"
+
+#endif	/* __USER_VERSION_H__ */
--- a/app/lua/lmathlib.c
+++ b/app/lua/lmathlib.c
@ -324,36 +324,36 @@ const LUA_REG_TYPE math_map[] = {
 #endif
 #else
  {LSTRKEY("abs"),   LFUNCVAL(math_abs)},
-  {LSTRKEY("acos"),  LFUNCVAL(math_acos)},
-  {LSTRKEY("asin"),  LFUNCVAL(math_asin)},
-  {LSTRKEY("atan2"), LFUNCVAL(math_atan2)},
-  {LSTRKEY("atan"),  LFUNCVAL(math_atan)},
+  // {LSTRKEY("acos"),  LFUNCVAL(math_acos)},
+  // {LSTRKEY("asin"),  LFUNCVAL(math_asin)},
+  // {LSTRKEY("atan2"), LFUNCVAL(math_atan2)},
+  // {LSTRKEY("atan"),  LFUNCVAL(math_atan)},
  {LSTRKEY("ceil"),  LFUNCVAL(math_ceil)},
-  {LSTRKEY("cosh"),  LFUNCVAL(math_cosh)},
-  {LSTRKEY("cos"),   LFUNCVAL(math_cos)},
-  {LSTRKEY("deg"),   LFUNCVAL(math_deg)},
-  {LSTRKEY("exp"),   LFUNCVAL(math_exp)},
+  // {LSTRKEY("cosh"),  LFUNCVAL(math_cosh)},
+  // {LSTRKEY("cos"),   LFUNCVAL(math_cos)},
+  // {LSTRKEY("deg"),   LFUNCVAL(math_deg)},
+  // {LSTRKEY("exp"),   LFUNCVAL(math_exp)},
  {LSTRKEY("floor"), LFUNCVAL(math_floor)},
-  {LSTRKEY("fmod"),  LFUNCVAL(math_fmod)},
+  // {LSTRKEY("fmod"),  LFUNCVAL(math_fmod)},
 #if LUA_OPTIMIZE_MEMORY > 0 && defined(LUA_COMPAT_MOD)
  {LSTRKEY("mod"),   LFUNCVAL(math_fmod)}, 
 #endif
-  {LSTRKEY("frexp"), LFUNCVAL(math_frexp)},
-  {LSTRKEY("ldexp"), LFUNCVAL(math_ldexp)},
-  {LSTRKEY("log10"), LFUNCVAL(math_log10)},
-  {LSTRKEY("log"),   LFUNCVAL(math_log)},
+  // {LSTRKEY("frexp"), LFUNCVAL(math_frexp)},
+  // {LSTRKEY("ldexp"), LFUNCVAL(math_ldexp)},
+  // {LSTRKEY("log10"), LFUNCVAL(math_log10)},
+  // {LSTRKEY("log"),   LFUNCVAL(math_log)},
  {LSTRKEY("max"),   LFUNCVAL(math_max)},
  {LSTRKEY("min"),   LFUNCVAL(math_min)},
-  {LSTRKEY("modf"),   LFUNCVAL(math_modf)},
+  // {LSTRKEY("modf"),   LFUNCVAL(math_modf)},
  {LSTRKEY("pow"),   LFUNCVAL(math_pow)},
-  {LSTRKEY("rad"),   LFUNCVAL(math_rad)},
+  // {LSTRKEY("rad"),   LFUNCVAL(math_rad)},
  {LSTRKEY("random"),     LFUNCVAL(math_random)},
  {LSTRKEY("randomseed"), LFUNCVAL(math_randomseed)},
-  {LSTRKEY("sinh"),   LFUNCVAL(math_sinh)},
-  {LSTRKEY("sin"),   LFUNCVAL(math_sin)},
+  // {LSTRKEY("sinh"),   LFUNCVAL(math_sinh)},
+  // {LSTRKEY("sin"),   LFUNCVAL(math_sin)},
  {LSTRKEY("sqrt"),  LFUNCVAL(math_sqrt)},
-  {LSTRKEY("tanh"),   LFUNCVAL(math_tanh)},
-  {LSTRKEY("tan"),   LFUNCVAL(math_tan)},
+  // {LSTRKEY("tanh"),   LFUNCVAL(math_tanh)},
+  // {LSTRKEY("tan"),   LFUNCVAL(math_tan)},
 #if LUA_OPTIMIZE_MEMORY > 0
  {LSTRKEY("pi"),    LNUMVAL(PI)},
  {LSTRKEY("huge"),  LNUMVAL(HUGE_VAL)},
--- a/app/lua/lua.c
+++ b/app/lua/lua.c
@ -10,6 +10,7 @@
 #include "c_stdlib.h"
 #include "c_string.h"
 #include "flash_fs.h"
+#include "user_version.h"

 #define lua_c

--- a/app/lua/lualib.h
+++ b/app/lua/lualib.h
@ -24,17 +24,17 @@ LUALIB_API int (luaopen_table) (lua_State *L);
 #define LUA_IOLIBNAME	"io"
 LUALIB_API int (luaopen_io) (lua_State *L);

-// #define LUA_OSLIBNAME	"os"
-// LUALIB_API int (luaopen_os) (lua_State *L);
+#define LUA_OSLIBNAME	"os"
+LUALIB_API int (luaopen_os) (lua_State *L);

 #define LUA_STRLIBNAME	"string"
 LUALIB_API int (luaopen_string) (lua_State *L);

-// #define LUA_MATHLIBNAME	"math"
-// LUALIB_API int (luaopen_math) (lua_State *L);
+#define LUA_MATHLIBNAME	"math"
+LUALIB_API int (luaopen_math) (lua_State *L);

-// #define LUA_DBLIBNAME	"debug"
-// LUALIB_API int (luaopen_debug) (lua_State *L);
+#define LUA_DBLIBNAME	"debug"
+LUALIB_API int (luaopen_debug) (lua_State *L);

 #define LUA_LOADLIBNAME	"package"
 LUALIB_API int (luaopen_package) (lua_State *L);
--- a/app/modules/Makefile
+++ b/app/modules/Makefile
@ -39,6 +39,7 @@ endif
 INCLUDES := $(INCLUDES) -I $(PDIR)include
 INCLUDES += -I ./
 INCLUDES += -I ../libc
+INCLUDES += -I ../coap
 INCLUDES += -I ../mqtt
 INCLUDES += -I ../u8glib
 INCLUDES += -I ../lua
--- a/app/modules/auxmods.h
+++ b/app/modules/auxmods.h
@ -61,6 +61,9 @@ LUALIB_API int ( luaopen_i2c )( lua_State *L );
 #define AUXLIB_WIFI      "wifi"
 LUALIB_API int ( luaopen_wifi )( lua_State *L );

+#define AUXLIB_COAP      "coap"
+LUALIB_API int ( luaopen_coap )( lua_State *L );
+
 #define AUXLIB_MQTT      "mqtt"
 LUALIB_API int ( luaopen_mqtt )( lua_State *L );

--- a/app/modules/coap.c
+++ b/app/modules/coap.c
@ -0,0 +1,646 @@
+// Module for coapwork
+
+//#include "lua.h"
+#include "lualib.h"
+#include "lauxlib.h"
+#include "platform.h"
+#include "auxmods.h"
+#include "lrotable.h"
+
+#include "c_string.h"
+#include "c_stdlib.h"
+
+#include "c_types.h"
+#include "mem.h"
+#include "espconn.h"
+#include "driver/uart.h"
+
+#include "coap.h"
+#include "uri.h"
+#include "node.h"
+#include "coap_timer.h"
+#include "coap_io.h"
+#include "coap_server.h"
+
+coap_queue_t *gQueue = NULL;
+
+typedef struct lcoap_userdata
+{
+  lua_State *L;
+  struct espconn *pesp_conn;
+  int self_ref;
+}lcoap_userdata;
+
+static void coap_received(void *arg, char *pdata, unsigned short len)
+{
+  NODE_DBG("coap_received is called.\n");
+  struct espconn *pesp_conn = arg;
+  lcoap_userdata *cud = (lcoap_userdata *)pesp_conn->reverse;
+
+  static uint8_t buf[MAX_MESSAGE_SIZE+1] = {0}; // +1 for string '\0'
+  c_memset(buf, 0, sizeof(buf)); // wipe prev data
+
+  if (len > MAX_MESSAGE_SIZE) {
+    NODE_DBG("Request Entity Too Large.\n"); // NOTE: should response 4.13 to client...
+    return;
+  } else {
+    c_memcpy(buf, pdata, len);
+  }
+
+  size_t rsplen = coap_server_respond(buf, len, MAX_MESSAGE_SIZE+1);
+  espconn_sent(pesp_conn, (unsigned char *)buf, rsplen);
+
+  c_memset(buf, 0, sizeof(buf));
+}
+
+static void coap_sent(void *arg)
+{
+  NODE_DBG("coap_sent is called.\n");
+}
+
+// Lua: s = coap.create(function(conn))
+static int coap_create( lua_State* L, const char* mt )
+{
+  struct espconn *pesp_conn = NULL;
+  lcoap_userdata *cud;
+  unsigned type;
+  int stack = 1;
+
+  // create a object
+  cud = (lcoap_userdata *)lua_newuserdata(L, sizeof(lcoap_userdata));
+  // pre-initialize it, in case of errors
+  cud->self_ref = LUA_NOREF;
+  cud->pesp_conn = NULL;
+
+  // set its metatable
+  luaL_getmetatable(L, mt);
+  lua_setmetatable(L, -2);
+
+  // create the espconn struct
+  pesp_conn = (struct espconn *)c_zalloc(sizeof(struct espconn));
+  if(!pesp_conn)
+    return luaL_error(L, "not enough memory");
+
+  cud->pesp_conn = pesp_conn;
+
+  pesp_conn->type = ESPCONN_UDP;
+  pesp_conn->proto.tcp = NULL;
+  pesp_conn->proto.udp = NULL;
+
+  pesp_conn->proto.udp = (esp_udp *)c_zalloc(sizeof(esp_udp));
+  if(!pesp_conn->proto.udp){
+    c_free(pesp_conn);
+    cud->pesp_conn = pesp_conn = NULL;
+    return luaL_error(L, "not enough memory");
+  }
+  pesp_conn->state = ESPCONN_NONE;
+  NODE_DBG("UDP server/client is set.\n");
+
+  cud->L = L;
+  pesp_conn->reverse = cud;
+
+  NODE_DBG("coap_create is called.\n");
+  return 1;  
+}
+
+// Lua: server:delete()
+static int coap_delete( lua_State* L, const char* mt )
+{
+  struct espconn *pesp_conn = NULL;
+  lcoap_userdata *cud;
+
+  cud = (lcoap_userdata *)luaL_checkudata(L, 1, mt);
+  luaL_argcheck(L, cud, 1, "Server/Client expected");
+  if(cud==NULL){
+    NODE_DBG("userdata is nil.\n");
+    return 0;
+  }
+
+  // free (unref) callback ref
+  if(LUA_NOREF!=cud->self_ref){
+    luaL_unref(L, LUA_REGISTRYINDEX, cud->self_ref);
+    cud->self_ref = LUA_NOREF;
+  }
+
+  cud->L = NULL;
+  if(cud->pesp_conn)
+  {
+    if(cud->pesp_conn->proto.udp->remote_port || cud->pesp_conn->proto.udp->local_port)
+      espconn_delete(cud->pesp_conn);
+    c_free(cud->pesp_conn->proto.udp);
+    cud->pesp_conn->proto.udp = NULL;
+    c_free(cud->pesp_conn);
+    cud->pesp_conn = NULL;
+  }
+
+  NODE_DBG("coap_delete is called.\n");
+  return 0;  
+}
+
+// Lua: server:listen( port, ip )
+static int coap_start( lua_State* L, const char* mt )
+{
+  struct espconn *pesp_conn = NULL;
+  lcoap_userdata *cud;
+  unsigned port;
+  size_t il;
+  ip_addr_t ipaddr;
+
+  cud = (lcoap_userdata *)luaL_checkudata(L, 1, mt);
+  luaL_argcheck(L, cud, 1, "Server/Client expected");
+  if(cud==NULL){
+    NODE_DBG("userdata is nil.\n");
+    return 0;
+  }
+
+  pesp_conn = cud->pesp_conn;
+  port = luaL_checkinteger( L, 2 );
+  pesp_conn->proto.udp->local_port = port;
+  NODE_DBG("UDP port is set: %d.\n", port);
+
+  if( lua_isstring(L,3) )   // deal with the ip string
+  {
+    const char *ip = luaL_checklstring( L, 3, &il );
+    if (ip == NULL)
+    {
+      ip = "0.0.0.0";
+    }
+    ipaddr.addr = ipaddr_addr(ip);
+    c_memcpy(pesp_conn->proto.udp->local_ip, &ipaddr.addr, 4);
+    NODE_DBG("UDP ip is set: ");
+    NODE_DBG(IPSTR, IP2STR(&ipaddr.addr));
+    NODE_DBG("\n");
+  }
+
+  if(LUA_NOREF==cud->self_ref){
+    lua_pushvalue(L, 1);  // copy to the top of stack
+    cud->self_ref = luaL_ref(L, LUA_REGISTRYINDEX);
+  }
+
+  espconn_regist_recvcb(pesp_conn, coap_received);
+  espconn_regist_sentcb(pesp_conn, coap_sent);
+  espconn_create(pesp_conn);
+
+  NODE_DBG("Coap Server started on port: %d\n", port);
+  NODE_DBG("coap_start is called.\n");
+  return 0;  
+}
+
+// Lua: server:close()
+static int coap_close( lua_State* L, const char* mt )
+{
+  struct espconn *pesp_conn = NULL;
+  lcoap_userdata *cud;
+
+  cud = (lcoap_userdata *)luaL_checkudata(L, 1, mt);
+  luaL_argcheck(L, cud, 1, "Server/Client expected");
+  if(cud==NULL){
+    NODE_DBG("userdata is nil.\n");
+    return 0;
+  }
+
+  if(cud->pesp_conn)
+  {
+    if(cud->pesp_conn->proto.udp->remote_port || cud->pesp_conn->proto.udp->local_port)
+      espconn_delete(cud->pesp_conn);
+  }
+
+  if(LUA_NOREF!=cud->self_ref){
+    luaL_unref(L, LUA_REGISTRYINDEX, cud->self_ref);
+    cud->self_ref = LUA_NOREF;
+  }
+
+  NODE_DBG("coap_close is called.\n");
+  return 0;  
+}
+
+// Lua: server/client:on( "method", function(s) )
+static int coap_on( lua_State* L, const char* mt )
+{
+  NODE_DBG("coap_on is called.\n");
+  return 0;  
+}
+
+static void coap_response_handler(void *arg, char *pdata, unsigned short len)
+{
+  NODE_DBG("coap_response_handler is called.\n");
+  struct espconn *pesp_conn = arg;
+
+  coap_packet_t pkt;
+  static uint8_t buf[MAX_MESSAGE_SIZE+1] = {0}; // +1 for string '\0'
+  c_memset(buf, 0, sizeof(buf)); // wipe prev data
+  static int n = 0;
+
+  int rc;
+  if ((len == 1460) && (1460 <= MAX_MESSAGE_SIZE)){
+    c_memcpy(buf, pdata, len); // max length is 1460, another part of data is coming in next callback
+    n = len;
+    return;
+  } else {
+    if( len > MAX_MESSAGE_SIZE )
+    {
+      NODE_DBG("Request Entity Too Large.\n"); // NOTE: should response 4.13 to client...
+      c_memset(buf, 0, sizeof(buf)); // wipe prev data
+      n = 0;
+      return;
+    }
+    c_memcpy(buf + n, pdata, len);
+    len += n; // more than 1460
+  }
+
+  if (0 != (rc = coap_parse(&pkt, buf, len))){
+    NODE_DBG("Bad packet rc=%d\n", rc);
+  }
+  else
+  {
+#ifdef COAP_DEBUG
+    coap_dumpPacket(&pkt);
+#endif
+    /* check if this is a response to our original request */
+    if (!check_token(&pkt)) {
+      /* drop if this was just some message, or send RST in case of notification */
+      if (pkt.hdr.t == COAP_TYPE_CON || pkt.hdr.t == COAP_TYPE_NONCON){
+        // coap_send_rst(pkt);  // send RST response
+        // or, just ignore it.
+      }
+      goto end;
+    }
+
+    if (pkt.hdr.t == COAP_TYPE_RESET) {
+      NODE_DBG("got RST\n");
+      goto end;
+    }
+
+    uint32_t ip = 0, port = 0;
+    coap_tid_t id = COAP_INVALID_TID;
+
+    c_memcpy(&ip, pesp_conn->proto.udp->remote_ip, sizeof(ip));
+    port = pesp_conn->proto.udp->remote_port;
+
+    coap_transaction_id(ip, port, &pkt, &id);
+
+    /* transaction done, remove the node from queue */
+    // stop timer
+    coap_timer_stop();
+    // remove the node
+    coap_remove_node(&gQueue, id);
+    // calculate time elapsed
+    coap_timer_update(&gQueue);
+    coap_timer_start(&gQueue);
+
+    if (COAP_RESPONSE_CLASS(pkt.hdr.code) == 2)
+    {
+      /* There is no block option set, just read the data and we are done. */
+      NODE_DBG("%d.%02d\t", (pkt.hdr.code >> 5), pkt.hdr.code & 0x1F);
+      NODE_DBG((char *)pkt.payload.p);
+    }
+    else if (COAP_RESPONSE_CLASS(pkt.hdr.code) >= 4)
+    {
+      NODE_DBG("%d.%02d\t", (pkt.hdr.code >> 5), pkt.hdr.code & 0x1F);
+      NODE_DBG((char *)pkt.payload.p);
+    }
+  }
+
+end:
+  if(!gQueue){ // if there is no node pending in the queue, disconnect from host.
+    if(pesp_conn->proto.udp->remote_port || pesp_conn->proto.udp->local_port)
+      espconn_delete(pesp_conn);
+  }
+  c_memset(buf, 0, sizeof(buf));
+  n = 0;
+}
+
+// Lua: client:request( [CON], uri, [payload] )
+static int coap_request( lua_State* L, coap_method_t m )
+{
+  struct espconn *pesp_conn = NULL;
+  lcoap_userdata *cud;
+  int stack = 1;
+
+  cud = (lcoap_userdata *)luaL_checkudata(L, stack, "coap_client");
+  luaL_argcheck(L, cud, stack, "Server/Client expected");
+  if(cud==NULL){
+    NODE_DBG("userdata is nil.\n");
+    return 0;
+  }
+
+  stack++;
+  pesp_conn = cud->pesp_conn;
+  ip_addr_t ipaddr;
+  uint8_t host[32];
+
+  unsigned t;
+  if ( lua_isnumber(L, stack) )
+  {
+    t = lua_tointeger(L, stack);
+    stack++;
+    if ( t != COAP_TYPE_CON && t != COAP_TYPE_NONCON )
+      return luaL_error( L, "wrong arg type" );
+  } else {
+    t = COAP_TYPE_CON; // default to CON
+  }
+
+  size_t l;
+  const char *url = luaL_checklstring( L, stack, &l );
+  stack++;
+  if (url == NULL)
+    return luaL_error( L, "wrong arg type" );
+
+  coap_uri_t *uri = coap_new_uri(url, l);   // should call free(uri) somewhere
+  if (uri == NULL)
+    return luaL_error( L, "uri wrong format." );
+
+  pesp_conn->proto.udp->remote_port = uri->port;
+  NODE_DBG("UDP port is set: %d.\n", uri->port);
+  pesp_conn->proto.udp->local_port = espconn_port();
+
+  if(uri->host.length){
+    c_memcpy(host, uri->host.s, uri->host.length);
+    host[uri->host.length] = '\0';
+
+    ipaddr.addr = ipaddr_addr(host);
+    NODE_DBG("Host len(%d):", uri->host.length);
+    NODE_DBG(host);
+    NODE_DBG("\n");
+
+    c_memcpy(pesp_conn->proto.udp->remote_ip, &ipaddr.addr, 4);
+    NODE_DBG("UDP ip is set: ");
+    NODE_DBG(IPSTR, IP2STR(&ipaddr.addr));
+    NODE_DBG("\n");
+  }
+
+  coap_pdu_t *pdu = coap_new_pdu();   // should call coap_delete_pdu() somewhere
+  if(!pdu){
+    if(uri)
+      c_free(uri);
+    return;
+  }
+
+  const char *payload = NULL;
+  l = 0;
+  if( lua_isstring(L, stack) ){
+    payload = luaL_checklstring( L, stack, &l );
+    if (payload == NULL)
+      l = 0;
+  }
+
+  coap_make_request(&(pdu->scratch), pdu->pkt, t, m, uri, payload, l);
+
+#ifdef COAP_DEBUG
+  coap_dumpPacket(pdu->pkt);
+#endif
+
+  int rc;
+  if (0 != (rc = coap_build(pdu->msg.p, &(pdu->msg.len), pdu->pkt))){
+    NODE_DBG("coap_build failed rc=%d\n", rc);
+  }
+  else
+  {
+#ifdef COAP_DEBUG
+    NODE_DBG("Sending: ");
+    coap_dump(pdu->msg.p, pdu->msg.len, true);
+    NODE_DBG("\n");
+#endif
+    espconn_regist_recvcb(pesp_conn, coap_response_handler);
+    sint8_t con = espconn_create(pesp_conn);
+    if( ESPCONN_OK != con){
+      NODE_DBG("Connect to host. code:%d\n", con);
+      // coap_delete_pdu(pdu);
+    } 
+    // else 
+    {
+      coap_tid_t tid = COAP_INVALID_TID;
+      if (pdu->pkt->hdr.t == COAP_TYPE_CON){
+        tid = coap_send_confirmed(pesp_conn, pdu);
+      }
+      else {
+        tid = coap_send(pesp_conn, pdu);
+      }
+      if (pdu->pkt->hdr.t != COAP_TYPE_CON || tid == COAP_INVALID_TID){
+        coap_delete_pdu(pdu);
+      }
+    }
+  }
+
+  if(uri)
+    c_free((void *)uri);
+
+  NODE_DBG("coap_request is called.\n");
+  return 0;  
+}
+
+extern coap_luser_entry *variable_entry;
+extern coap_luser_entry *function_entry;
+extern void build_well_known_rsp(void);
+// Lua: coap:var/func( string )
+static int coap_regist( lua_State* L, const char* mt, int isvar )
+{
+  size_t l;
+  const char *name = luaL_checklstring( L, 2, &l );
+  if (name == NULL)
+    return luaL_error( L, "name must be set." );
+
+  coap_luser_entry *h = NULL;
+  // if(lua_isstring(L, 3))
+  if(isvar)
+    h = variable_entry;
+  else
+    h = function_entry;
+
+  while(NULL!=h->next){  // goto the end of the list
+    if(h->name!= NULL && c_strcmp(h->name, name)==0)  // key exist, override it
+      break;
+    h = h->next;
+  }
+
+  if(h->name==NULL || c_strcmp(h->name, name)!=0){   // not exists. make a new one.
+    h->next = (coap_luser_entry *)c_zalloc(sizeof(coap_luser_entry));
+    h = h->next;
+    if(h == NULL)
+      return luaL_error(L, "not enough memory");
+    h->next = NULL;
+    h->name = NULL;
+    h->L = NULL;
+  }  
+
+  h->L = L;
+  h->name = name;
+
+  build_well_known_rsp(); // rebuild .well-known
+
+  NODE_DBG("coap_regist is called.\n");
+  return 0;  
+}
+
+// Lua: s = coap.createServer(function(conn))
+static int coap_createServer( lua_State* L )
+{
+  const char *mt = "coap_server";
+  return coap_create(L, mt);
+}
+
+// Lua: server:delete()
+static int coap_server_delete( lua_State* L )
+{
+  const char *mt = "coap_server";
+  return coap_delete(L, mt);
+}
+
+// Lua: server:listen( port, ip, function(err) )
+static int coap_server_listen( lua_State* L )
+{
+  const char *mt = "coap_server";
+  return coap_start(L, mt);
+}
+
+// Lua: server:close()
+static int coap_server_close( lua_State* L )
+{
+  const char *mt = "coap_server";
+  return coap_close(L, mt);
+}
+
+// Lua: server:on( "method", function(server) )
+static int coap_server_on( lua_State* L )
+{
+  const char *mt = "coap_server";
+  return coap_on(L, mt);
+}
+
+// Lua: server:var( "name" )
+static int coap_server_var( lua_State* L )
+{
+  const char *mt = "coap_server";
+  return coap_regist(L, mt, 1);
+}
+
+// Lua: server:func( "name" )
+static int coap_server_func( lua_State* L )
+{
+  const char *mt = "coap_server";
+  return coap_regist(L, mt, 0);
+}
+
+// Lua: s = coap.createClient(function(conn))
+static int coap_createClient( lua_State* L )
+{
+  const char *mt = "coap_client";
+  return coap_create(L, mt);
+}
+
+// Lua: client:gcdelete()
+static int coap_client_gcdelete( lua_State* L )
+{
+  const char *mt = "coap_client";
+  return coap_delete(L, mt);
+}
+
+// client:get( string, function(sent) )
+static int coap_client_get( lua_State* L )
+{
+  return coap_request(L, COAP_METHOD_GET);
+}
+
+// client:post( string, function(sent) )
+static int coap_client_post( lua_State* L )
+{
+  return coap_request(L, COAP_METHOD_POST);
+}
+
+// client:put( string, function(sent) )
+static int coap_client_put( lua_State* L )
+{
+  return coap_request(L, COAP_METHOD_PUT);
+}
+
+// client:delete( string, function(sent) )
+static int coap_client_delete( lua_State* L )
+{
+  return coap_request(L, COAP_METHOD_DELETE);
+}
+
+// Module function map
+#define MIN_OPT_LEVEL 2
+#include "lrodefs.h"
+static const LUA_REG_TYPE coap_server_map[] =
+{
+  { LSTRKEY( "listen" ), LFUNCVAL ( coap_server_listen ) },
+  { LSTRKEY( "close" ), LFUNCVAL ( coap_server_close ) },
+  { LSTRKEY( "var" ), LFUNCVAL ( coap_server_var ) },
+  { LSTRKEY( "func" ), LFUNCVAL ( coap_server_func ) },
+  { LSTRKEY( "__gc" ), LFUNCVAL ( coap_server_delete ) },
+#if LUA_OPTIMIZE_MEMORY > 0
+  { LSTRKEY( "__index" ), LROVAL ( coap_server_map ) },
+#endif
+  { LNILKEY, LNILVAL }
+};
+
+static const LUA_REG_TYPE coap_client_map[] =
+{
+  { LSTRKEY( "get" ), LFUNCVAL ( coap_client_get ) },
+  { LSTRKEY( "post" ), LFUNCVAL ( coap_client_post ) },
+  { LSTRKEY( "put" ), LFUNCVAL ( coap_client_put ) },
+  { LSTRKEY( "delete" ), LFUNCVAL ( coap_client_delete ) },
+  { LSTRKEY( "__gc" ), LFUNCVAL ( coap_client_gcdelete ) },
+#if LUA_OPTIMIZE_MEMORY > 0
+  { LSTRKEY( "__index" ), LROVAL ( coap_client_map ) },
+#endif
+  { LNILKEY, LNILVAL }
+};
+
+const LUA_REG_TYPE coap_map[] = 
+{
+  { LSTRKEY( "Server" ), LFUNCVAL ( coap_createServer ) },
+  { LSTRKEY( "Client" ), LFUNCVAL ( coap_createClient ) },
+#if LUA_OPTIMIZE_MEMORY > 0
+  { LSTRKEY( "CON" ), LNUMVAL( COAP_TYPE_CON ) },
+  { LSTRKEY( "NON" ), LNUMVAL( COAP_TYPE_NONCON ) },
+
+  { LSTRKEY( "__metatable" ), LROVAL( coap_map ) },
+#endif
+  { LNILKEY, LNILVAL }
+};
+
+LUALIB_API int luaopen_coap( lua_State *L )
+{
+  endpoint_setup();
+#if LUA_OPTIMIZE_MEMORY > 0
+  luaL_rometatable(L, "coap_server", (void *)coap_server_map);  // create metatable for coap_server 
+  luaL_rometatable(L, "coap_client", (void *)coap_client_map);  // create metatable for coap_client  
+  return 0;
+#else // #if LUA_OPTIMIZE_MEMORY > 0
+  int n;
+  luaL_register( L, AUXLIB_COAP, coap_map );
+
+  // Set it as its own metatable
+  lua_pushvalue( L, -1 );
+  lua_setmetatable( L, -2 );
+
+  // Module constants  
+  MOD_REG_NUMBER( L, "CON", COAP_TYPE_CON );
+  MOD_REG_NUMBER( L, "NON", COAP_TYPE_NONCON );
+
+  n = lua_gettop(L);
+
+  // create metatable
+  luaL_newmetatable(L, "coap_server");
+  // metatable.__index = metatable
+  lua_pushliteral(L, "__index");
+  lua_pushvalue(L,-2);
+  lua_rawset(L,-3);
+  // Setup the methods inside metatable
+  luaL_register( L, NULL, coap_server_map );
+
+  lua_settop(L, n);
+  // create metatable
+  luaL_newmetatable(L, "coap_client");
+  // metatable.__index = metatable
+  lua_pushliteral(L, "__index");
+  lua_pushvalue(L,-2);
+  lua_rawset(L,-3);
+  // Setup the methods inside metatable
+  luaL_register( L, NULL, coap_client_map );
+
+  return 1;
+#endif // #if LUA_OPTIMIZE_MEMORY > 0  
+}
--- a/app/modules/linit.c
+++ b/app/modules/linit.c
@ -15,6 +15,8 @@
 #include "lrotable.h"
 #include "luaconf.h"

+#include "user_modules.h"
+
 #if defined(LUA_USE_MODULES)
 #include "modules.h"
 #endif
@ -28,12 +30,26 @@ LUA_MODULES_ROM
 static const luaL_Reg lualibs[] = {
  {"", luaopen_base},
  {LUA_LOADLIBNAME, luaopen_package},
-  // {LUA_IOLIBNAME, luaopen_io},
+#if defined(LUA_USE_BUILTIN_IO)
+  {LUA_IOLIBNAME, luaopen_io},
+#endif
+
+#if defined(LUA_USE_BUILTIN_STRING)
  {LUA_STRLIBNAME, luaopen_string},
+#endif
+
 #if LUA_OPTIMIZE_MEMORY == 0
-  // {LUA_MATHLIBNAME, luaopen_math},
+  #if defined(LUA_USE_BUILTIN_MATH)
+  {LUA_MATHLIBNAME, luaopen_math},
+  #endif
+
+  #if defined(LUA_USE_BUILTIN_TABLE)
  {LUA_TABLIBNAME, luaopen_table},  
-  // {LUA_DBLIBNAME, luaopen_debug},  
+  #endif
+
+  #if defined(LUA_USE_BUILTIN_DEBUG)
+  {LUA_DBLIBNAME, luaopen_debug},
+  #endif 
 #endif
 #if defined(LUA_MODULES_ROM)
 #undef _ROM
@ -43,12 +59,30 @@ static const luaL_Reg lualibs[] = {
  {NULL, NULL}
 };

+#if defined(LUA_USE_BUILTIN_STRING)
 extern const luaR_entry strlib[];
+#endif
+
+#if defined(LUA_USE_BUILTIN_OS)
 extern const luaR_entry syslib[];
+#endif
+
+#if defined(LUA_USE_BUILTIN_TABLE)
 extern const luaR_entry tab_funcs[];
-// extern const luaR_entry dblib[];
+#endif
+
+#if defined(LUA_USE_BUILTIN_DEBUG)
+extern const luaR_entry dblib[];
+#endif
+
+#if defined(LUA_USE_BUILTIN_COROUTINE)
 extern const luaR_entry co_funcs[];
-// extern const luaR_entry math_map[];
+#endif
+
+#if defined(LUA_USE_BUILTIN_MATH)
+extern const luaR_entry math_map[];
+#endif
+
 #if defined(LUA_MODULES_ROM) && LUA_OPTIMIZE_MEMORY == 2
 #undef _ROM
 #define _ROM( name, openf, table ) extern const luaR_entry table[];
@ -57,11 +91,30 @@ LUA_MODULES_ROM
 const luaR_table lua_rotable[] = 
 {
 #if LUA_OPTIMIZE_MEMORY > 0
+  #if defined(LUA_USE_BUILTIN_STRING)
  {LUA_STRLIBNAME, strlib},
+  #endif
+
+  #if defined(LUA_USE_BUILTIN_TABLE)
  {LUA_TABLIBNAME, tab_funcs},
-  // {LUA_DBLIBNAME, dblib},
+  #endif
+
+  #if defined(LUA_USE_BUILTIN_DEBUG)
+  {LUA_DBLIBNAME, dblib},
+  #endif
+
+  #if defined(LUA_USE_BUILTIN_COROUTINE)
  {LUA_COLIBNAME, co_funcs},
-  // {LUA_MATHLIBNAME, math_map},
+  #endif
+
+  #if defined(LUA_USE_BUILTIN_MATH)
+  {LUA_MATHLIBNAME, math_map},
+  #endif
+
+  #if defined(LUA_USE_BUILTIN_OS)
+  {LUA_OSLIBNAME, syslib},
+  #endif
+
 #if defined(LUA_MODULES_ROM) && LUA_OPTIMIZE_MEMORY == 2
 #undef _ROM
 #define _ROM( name, openf, table ) { name, table },
--- a/app/modules/modules.h
+++ b/app/modules/modules.h
@ -37,6 +37,14 @@
 #define ROM_MODULES_NET
 #endif

+#if defined(LUA_USE_MODULES_COAP)
+#define MODULES_COAP       "coap"
+#define ROM_MODULES_COAP   \
+    _ROM(MODULES_COAP, luaopen_coap, coap_map)
+#else
+#define ROM_MODULES_COAP
+#endif
+
 #if defined(LUA_USE_MODULES_MQTT)
 #define MODULES_MQTT       "mqtt"
 #define ROM_MODULES_MQTT   \
@ -136,8 +144,9 @@

 #define LUA_MODULES_ROM     \
        ROM_MODULES_GPIO    \
-        ROM_MODULES_PWM     \
-        ROM_MODULES_WIFI    \
+        ROM_MODULES_PWM		\
+        ROM_MODULES_WIFI	\
+        ROM_MODULES_COAP	\
        ROM_MODULES_MQTT    \
        ROM_MODULES_U8G     \
        ROM_MODULES_I2C     \
--- a/app/modules/mqtt.c
+++ b/app/modules/mqtt.c
@ -1102,7 +1102,7 @@ const LUA_REG_TYPE mqtt_map[] =
  { LNILKEY, LNILVAL }
 };

-LUALIB_API int ICACHE_FLASH_ATTR luaopen_mqtt( lua_State *L )
+LUALIB_API int luaopen_mqtt( lua_State *L )
 {
 #if LUA_OPTIMIZE_MEMORY > 0
  luaL_rometatable(L, "mqtt.socket", (void *)mqtt_socket_map);  // create metatable for mqtt.socket
--- a/app/modules/node.c
+++ b/app/modules/node.c
@ -23,6 +23,7 @@
 #include "user_interface.h"
 #include "flash_api.h"
 #include "flash_fs.h"
+#include "user_version.h"

 // Lua: restart()
 static int node_restart( lua_State* L )
--- a/examples/fragment.lua
+++ b/examples/fragment.lua
@ -347,3 +347,19 @@ file.close()
 node.compile("hello.lua")
 dofile("hello.lua")
 dofile("hello.lc")
+
+-- use copper addon for firefox
+cs=coap.Server()
+cs:listen(5683)
+
+myvar=1
+cs:var("myvar") -- get coap://192.168.18.103:5683/v1/v/myvar will return the value of myvar: 1
+
+function myfun()
+	print("myfun called")
+end
+cs:func("myfun") -- post coap://192.168.18.103:5683/v1/f/myfun will call myfun
+
+cc = coap.Client()
+cc:get(coap.CON, "coap://192.168.18.100:5683/.well-known/core")
+cc:post(coap.NON, "coap://192.168.18.100:5683/", "Hello")
--- a/ld/eagle.app.v6.ld
+++ b/ld/eagle.app.v6.ld
@ -5,7 +5,7 @@ MEMORY
  dport0_0_seg :                      	org = 0x3FF00000, len = 0x10
  dram0_0_seg :                       	org = 0x3FFE8000, len = 0x14000
  iram1_0_seg :                       	org = 0x40100000, len = 0x8000
-  irom0_0_seg :                       	org = 0x40210000, len = 0x55000
+  irom0_0_seg :                       	org = 0x40210000, len = 0x5A000
 }

 PHDRS
--- a/lib/libm.a
+++ b/lib/libm.a
--- a/lua_modules/hdc1000/HDC1000-example.lua
+++ b/lua_modules/hdc1000/HDC1000-example.lua
@ -0,0 +1,12 @@
+HDC1000 = require("HDC1000")
+
+sda = 1
+scl = 2
+
+HDC1000.init(sda, scl)
+HDC1000.config() -- default values are used if called with no arguments. prototype is config(address, resolution, heater)
+
+print(string.format("Temperature: %.2f °C\nHumidity: %.2f %%", HDC1000.getTemp(), HDC1000.getHumi()))
+
+HDC1000 = nil
+package.loaded["HDC1000"]=nil
--- a/lua_modules/hdc1000/HDC1000.lua
+++ b/lua_modules/hdc1000/HDC1000.lua
@ -0,0 +1,99 @@
+-------------------------------------------------------
+
+-- This library was written for the Texas Instruments 
+-- HDC1000 temperature and humidity sensor. 
+-- It should work for the HDC1008 too.
+-- Written by Francesco Truzzi (francesco@truzzi.me)
+-- Released under GNU GPL v2.0 license.
+
+-------------------------------------------------------
+
+-------------- NON-DEFAULT CONFIG VALUES --------------
+------------- config() optional arguments -------------
+
+--	HDC1000_HEAT_OFF			0x00	(heater)
+--	HDC1000_TEMP_11BIT			0x40	(resolution)
+-- 	HDC1000_HUMI_11BIT			0x01 	(resolution)
+--	HDC1000_HUMI_8BIT			0x20 	(resolution)
+
+-------------------------------------------------------
+
+local modname = ...
+local M = {}
+_G[modname] = M
+
+local id = 0
+local i2c = i2c
+local delay = 20000
+
+local HDC1000_ADDR = 0x40
+
+local HDC1000_TEMP = 0x00
+local HDC1000_HUMI = 0x01
+local HDC1000_CONFIG = 0x02
+
+local HDC1000_HEAT_ON = 0x20
+local HDC1000_TEMP_HUMI_14BIT = 0x00
+
+-- reads 16bits from the sensor
+local function read16()
+	i2c.start(id)
+	i2c.address(id, HDC1000_ADDR, i2c.RECEIVER)
+	data_temp = i2c.read(0, 2)
+	i2c.stop(id)
+	data = bit.lshift(string.byte(data_temp, 1, 1), 8) + string.byte(data_temp, 2, 2)
+	return data
+end
+
+-- sets the register to read next
+local function setReadRegister(register)
+	i2c.start(id)
+	i2c.address(id, HDC1000_ADDR, i2c.TRANSMITTER)
+	i2c.write(id, register)
+	i2c.stop(id)
+end
+
+-- writes the 2 configuration bytes
+local function writeConfig(config)
+	i2c.start(id)
+	i2c.address(id, HDC1000_ADDR, i2c.TRANSMITTER)
+	i2c.write(id, HDC1000_CONFIG, config, 0x00)
+	i2c.stop(id)
+end
+
+-- returns true if battery voltage is < 2.7V, false otherwise
+function M.batteryDead()
+	setReadRegister(HDC1000_CONFIG)
+	return(bit.isset(read16(), 11))
+
+end
+
+-- initalize i2c
+function M.init(sda, scl)
+	i2c.setup(id, sda, scl, i2c.SLOW)
+end
+
+function M.config(addr, resolution, heater)
+	-- default values are set if the function is called with no arguments
+	HDC1000_ADDR = addr or HDC1000_ADDR
+	resolution = resolution or HDC1000_TEMP_HUMI_14BIT
+	heater = heater or HDC1000_HEAT_ON
+	writeConfig(bit.bor(resolution, heater))
+end
+
+-- outputs temperature in Celsius degrees
+function M.getHumi()
+	setReadRegister(HDC1000_HUMI)
+	tmr.delay(delay)
+	return(read16()/65535.0*100)
+end
+
+-- outputs humidity in %RH
+function M.getTemp()
+	setReadRegister(HDC1000_TEMP)
+	tmr.delay(delay)
+	return(read16()/65535.0*165-40)
+end
+
+return M
+
--- a/lua_modules/hdc1000/README.md
+++ b/lua_modules/hdc1000/README.md
@ -0,0 +1,39 @@
+HDC1000 NodeMCU module
+=======================
+
+Here's my NodeMCU module for the TI HDC1000 temperature and humidity sensor. It should work with the HDC1008 too but I haven't tested it.
+
+### Setup your sensor:
+First, require it:
+
+`HDC1000 = require("HDC1000")`
+
+Then, initialize it:
+
+`HDC1000.init(sda, scl)`
+
+Configure it:
+
+`HDC1000.config()`
+
+Default options set the address to 0x40 and enable both temperature and humidity readings at 14-bit resolution, with the integrated heater on. You can change them by initializing your sensor like this:
+
+`HDC1000.config(address, resolution, heater);`
+
+"resolution" can be set to 14 bits for both temperature and humidity (0x00 - default) 11 bits for temperature (0x40), 11 bits for humidity (0x01), 8 bits for humidity (0x20)
+"heater" can be set to ON (0x20 - default) or OFF (0x00)
+
+### Read some values
+You can read temperature and humidity by using the following commands:
+
+`temperature = HDC1000.getTemp()` in Celsius degrees.
+
+`humidity = HDC1000.getHumi()` in %
+
+### Check your battery
+
+The following code returns true if the battery voltage is <2.8V, false otherwise.
+
+`isDead = HDC1000.batteryDead();`
+
+Happy making! Also, check out my Breakout Board and Arduino library for this chip: http://b.truzzi.me/hdc1000-temperature-and-humidity-sensor-breakout-with-arduino-library/.