nodemcu-firmware/app/modules/ds18b20.c

306 lines
9.7 KiB
C

//***************************************************************************
// DS18B20 module for ESP8266 with nodeMCU
// fetchbot @github
// MIT license, http://opensource.org/licenses/MIT
//***************************************************************************
#include "module.h"
#include "lauxlib.h"
#include "platform.h"
#include "osapi.h"
#include "driver/onewire.h"
#include "c_stdio.h"
#include "c_stdlib.h"
//***************************************************************************
// OW ROM COMMANDS
//***************************************************************************
#define DS18B20_ROM_SEARCH (0xF0)
#define DS18B20_ROM_READ (0x33)
#define DS18B20_ROM_MATCH (0x55)
#define DS18B20_ROM_SKIP (0xCC)
#define DS18B20_ROM_SEARCH_ALARM (0xEC)
//***************************************************************************
// OW FUNCTION COMMANDS
//***************************************************************************
#define DS18B20_FUNC_CONVERT (0x44)
#define DS18B20_FUNC_SCRATCH_WRITE (0x4E)
#define DS18B20_FUNC_SCRATCH_READ (0xBE)
#define DS18B20_FUNC_SCRATCH_COPY (0x48)
#define DS18B20_FUNC_E2_RECALL (0xB8)
#define DS18B20_FUNC_POWER_READ (0xB4)
//***************************************************************************
// Initial EEPROM values
//***************************************************************************
#define DS18B20_EEPROM_TH (0x4B) // 75 degree
#define DS18B20_EEPROM_TL (0x46) // 70 degree
#define DS18B20_EEPROM_RES (0x7F) // 12 bit resolution
//***************************************************************************
static uint8_t ds18b20_bus_pin;
static uint8_t ds18b20_device_family;
static uint8_t ds18b20_device_search = 0;
static uint8_t ds18b20_device_index;
static uint8_t ds18b20_device_par;
static uint8_t ds18b20_device_conf[3];
static uint8_t ds18b20_device_rom[8];
static uint8_t ds18b20_device_scratchpad[9];
static double ds18b20_device_scratchpad_temp;
static int ds18b20_device_scratchpad_temp_dec;
static uint8_t ds18b20_device_scratchpad_conf;
static uint8_t ds18b20_device_res = 12; // 12 bit resolution (750ms conversion time)
os_timer_t ds18b20_timer; // timer for conversion delay
int ds18b20_timer_ref; // callback when readout is ready
int ds18b20_table_ref;
static int ds18b20_table_offset;
static int ds18b20_lua_readoutdone(void);
// Setup onewire bus for DS18B20 temperature sensors
// Lua: ds18b20.setup(OW_BUS_PIN)
static int ds18b20_lua_setup(lua_State *L) {
platform_print_deprecation_note("ds18b20 C module superseded by Lua implementation", "soon");
// check ow bus pin value
if (!lua_isnumber(L, 1) || lua_isnumber(L, 1) == 0) {
return luaL_error(L, "wrong 1-wire pin");
}
ds18b20_bus_pin = luaL_checkinteger(L, 1);
MOD_CHECK_ID(ow, ds18b20_bus_pin);
onewire_init(ds18b20_bus_pin);
}
static int ds18b20_set_device(uint8_t *ds18b20_device_rom) {
onewire_reset(ds18b20_bus_pin);
onewire_select(ds18b20_bus_pin, ds18b20_device_rom);
onewire_write(ds18b20_bus_pin, DS18B20_FUNC_SCRATCH_WRITE, 0);
onewire_write_bytes(ds18b20_bus_pin, ds18b20_device_conf, 3, 0);
}
// Change sensor settings
// Lua: ds18b20.setting(ROM, RES)
static int ds18b20_lua_setting(lua_State *L) {
// check rom table and resolution setting
if (!lua_istable(L, 1) || !lua_isnumber(L, 2)) {
return luaL_error(L, "wrong arg range");
}
ds18b20_device_res = luaL_checkinteger(L, 2);
if (!((ds18b20_device_res == 9) || (ds18b20_device_res == 10) || (ds18b20_device_res == 11) || (ds18b20_device_res == 12))) {
return luaL_error(L, "Invalid argument: resolution");
}
// no change to th and tl setting
ds18b20_device_conf[0] = DS18B20_EEPROM_TH;
ds18b20_device_conf[1] = DS18B20_EEPROM_TL;
ds18b20_device_conf[2] = ((ds18b20_device_res - 9) << 5) + 0x1F;
uint8_t table_len = lua_objlen(L, 1);
const char *str[table_len];
const char *sep = ":";
uint8_t string_index = 0;
lua_pushnil(L);
while (lua_next(L, -3)) {
str[string_index] = lua_tostring(L, -1);
lua_pop(L, 1);
string_index++;
}
lua_pop(L, 1);
for (uint8_t i = 0; i < string_index; i++) {
for (uint8_t j = 0; j < 8; j++) {
ds18b20_device_rom[j] = strtoul(str[i], NULL, 16);
str[i] = strchr(str[i], *sep);
if (str[i] == NULL || *str[i] == '\0') break;
str[i]++;
}
ds18b20_set_device(ds18b20_device_rom);
}
// set conversion delay once to max if sensors with higher resolution still on the bus
ds18b20_device_res = 12;
return 0;
}
#include "pm/swtimer.h"
// Reads sensor values from all devices
// Lua: ds18b20.read(function(INDEX, ROM, RES, TEMP, TEMP_DEC, PAR) print(INDEX, ROM, RES, TEMP, TEMP_DEC, PAR) end, ROM[, FAMILY])
static int ds18b20_lua_read(lua_State *L) {
luaL_argcheck(L, (lua_type(L, 1) == LUA_TFUNCTION || lua_type(L, 1) == LUA_TLIGHTFUNCTION), 1, "Must be function");
lua_pushvalue(L, 1);
ds18b20_timer_ref = luaL_ref(L, LUA_REGISTRYINDEX);
if (!lua_istable(L, 2)) {
return luaL_error(L, "wrong arg range");
}
if (lua_isnumber(L, 3)) {
ds18b20_device_family = luaL_checkinteger(L, 3);
onewire_target_search(ds18b20_bus_pin, ds18b20_device_family);
ds18b20_table_offset = -3;
} else {
ds18b20_table_offset = -2;
}
lua_pushvalue(L, 2);
ds18b20_table_ref = luaL_ref(L, LUA_REGISTRYINDEX);
lua_pushnil(L);
if (lua_next(L, ds18b20_table_offset)) {
lua_pop(L, 2);
ds18b20_device_search = 0;
} else {
ds18b20_device_search = 1;
}
os_timer_disarm(&ds18b20_timer);
// perform a temperature conversion for all sensors and set timer
onewire_reset(ds18b20_bus_pin);
onewire_write(ds18b20_bus_pin, DS18B20_ROM_SKIP, 0);
onewire_write(ds18b20_bus_pin, DS18B20_FUNC_CONVERT, 1);
os_timer_setfn(&ds18b20_timer, (os_timer_func_t *)ds18b20_lua_readoutdone, NULL);
SWTIMER_REG_CB(ds18b20_lua_readoutdone, SWTIMER_DROP);
//The function ds18b20_lua_readoutdone reads the temperature from the sensor(s) after a set amount of time depending on temperature resolution
//MY guess: If this timer manages to get suspended before it fires and the temperature data is time sensitive then resulting data would be invalid and should be discarded
switch (ds18b20_device_res) {
case (9):
os_timer_arm(&ds18b20_timer, 95, 0);
break;
case (10):
os_timer_arm(&ds18b20_timer, 190, 0);
break;
case (11):
os_timer_arm(&ds18b20_timer, 380, 0);
break;
case (12):
os_timer_arm(&ds18b20_timer, 760, 0);
break;
}
}
static int ds18b20_read_device(uint8_t *ds18b20_device_rom) {
lua_State *L = lua_getstate();
int16_t ds18b20_raw_temp;
if (onewire_crc8(ds18b20_device_rom,7) == ds18b20_device_rom[7]) {
onewire_reset(ds18b20_bus_pin);
onewire_select(ds18b20_bus_pin, ds18b20_device_rom);
onewire_write(ds18b20_bus_pin, DS18B20_FUNC_POWER_READ, 0);
if (onewire_read(ds18b20_bus_pin)) ds18b20_device_par = 0;
else ds18b20_device_par = 1;
onewire_reset(ds18b20_bus_pin);
onewire_select(ds18b20_bus_pin, ds18b20_device_rom);
onewire_write(ds18b20_bus_pin, DS18B20_FUNC_SCRATCH_READ, 0);
onewire_read_bytes(ds18b20_bus_pin, ds18b20_device_scratchpad, 9);
if (onewire_crc8(ds18b20_device_scratchpad,8) == ds18b20_device_scratchpad[8]) {
lua_rawgeti(L, LUA_REGISTRYINDEX, ds18b20_timer_ref);
lua_pushinteger(L, ds18b20_device_index);
lua_pushfstring(L, "%d:%d:%d:%d:%d:%d:%d:%d", ds18b20_device_rom[0], ds18b20_device_rom[1], ds18b20_device_rom[2], ds18b20_device_rom[3], ds18b20_device_rom[4], ds18b20_device_rom[5], ds18b20_device_rom[6], ds18b20_device_rom[7]);
ds18b20_device_scratchpad_conf = (ds18b20_device_scratchpad[4] >> 5) + 9;
ds18b20_raw_temp = ((ds18b20_device_scratchpad[1] << 8) | ds18b20_device_scratchpad[0]);
ds18b20_device_scratchpad_temp = (double)ds18b20_raw_temp / 16;
ds18b20_device_scratchpad_temp_dec = (ds18b20_raw_temp - (ds18b20_raw_temp / 16 * 16)) * 1000 / 16;
if (ds18b20_device_scratchpad_conf >= ds18b20_device_res) {
ds18b20_device_res = ds18b20_device_scratchpad_conf;
}
lua_pushinteger(L, ds18b20_device_scratchpad_conf);
lua_pushnumber(L, ds18b20_device_scratchpad_temp);
lua_pushinteger(L, ds18b20_device_scratchpad_temp_dec);
lua_pushinteger(L, ds18b20_device_par);
lua_pcall(L, 6, 0, 0);
ds18b20_device_index++;
}
}
}
static int ds18b20_lua_readoutdone(void) {
lua_State *L = lua_getstate();
os_timer_disarm(&ds18b20_timer);
ds18b20_device_index = 1;
// set conversion delay to min and change it after finding the sensor with the highest resolution setting
ds18b20_device_res = 9;
if (ds18b20_device_search) {
// iterate through all sensors on the bus and read temperature, resolution and parasitc settings
while (onewire_search(ds18b20_bus_pin, ds18b20_device_rom)) {
ds18b20_read_device(ds18b20_device_rom);
}
} else {
lua_rawgeti(L, LUA_REGISTRYINDEX, ds18b20_table_ref);
uint8_t table_len = lua_objlen(L, -1);
const char *str[table_len];
const char *sep = ":";
uint8_t string_index = 0;
lua_pushnil(L);
while (lua_next(L, -2)) {
str[string_index] = lua_tostring(L, -1);
lua_pop(L, 1);
string_index++;
}
lua_pop(L, 1);
for (uint8_t i = 0; i < string_index; i++) {
for (uint8_t j = 0; j < 8; j++) {
ds18b20_device_rom[j] = strtoul(str[i], NULL, 16);
str[i] = strchr(str[i], *sep);
if (str[i] == NULL || *str[i] == '\0') break;
str[i]++;
}
ds18b20_read_device(ds18b20_device_rom);
}
}
luaL_unref(L, LUA_REGISTRYINDEX, ds18b20_table_ref);
ds18b20_table_ref = LUA_NOREF;
luaL_unref(L, LUA_REGISTRYINDEX, ds18b20_timer_ref);
ds18b20_timer_ref = LUA_NOREF;
}
static const LUA_REG_TYPE ds18b20_map[] = {
{ LSTRKEY( "read" ), LFUNCVAL(ds18b20_lua_read) },
{ LSTRKEY( "setting" ), LFUNCVAL(ds18b20_lua_setting) },
{ LSTRKEY( "setup" ), LFUNCVAL(ds18b20_lua_setup) },
{ LNILKEY, LNILVAL }
};
NODEMCU_MODULE(DS18B20, "ds18b20", ds18b20_map, NULL);