Added support for STM L3G4200D digital gyroscope (#1251)

app/include/user_modules.h

@@ -36,6 +36,7 @@
 //#define LUA_USE_MODULES_HTTP
 //#define LUA_USE_MODULES_HX711
 #define LUA_USE_MODULES_I2C
+//#define LUA_USE_MODULES_L3G4200D
 //#define LUA_USE_MODULES_MDNS
 #define LUA_USE_MODULES_MQTT
 #define LUA_USE_MODULES_NET

app/modules/l3g4200d.c

@@ -0,0 +1,98 @@
+/*
+ * Driver for STM L3G4200D three axis gyroscope
+ *
+ * Code based on BMP085 driver.
+ */
+#include "module.h"
+#include "lauxlib.h"
+#include "platform.h"
+#include "c_stdlib.h"
+#include "c_string.h"
+
+static const uint32_t i2c_id = 0;
+static const uint8_t i2c_addr = 0x69;
+
+static uint8_t ICACHE_FLASH_ATTR r8u(uint32_t id, uint8_t reg) {
+    uint8_t ret;
+
+    platform_i2c_send_start(id);
+    platform_i2c_send_address(id, i2c_addr, PLATFORM_I2C_DIRECTION_TRANSMITTER);
+    platform_i2c_send_byte(id, reg);
+    platform_i2c_send_stop(id);
+    platform_i2c_send_start(id);
+    platform_i2c_send_address(id, i2c_addr, PLATFORM_I2C_DIRECTION_RECEIVER);
+    ret = platform_i2c_recv_byte(id, 0);
+    platform_i2c_send_stop(id);
+    return ret;
+}
+
+static void ICACHE_FLASH_ATTR w8u(uint32_t id, uint8_t reg, uint8_t val) {
+    platform_i2c_send_start(i2c_id);
+    platform_i2c_send_address(i2c_id, i2c_addr, PLATFORM_I2C_DIRECTION_TRANSMITTER);
+    platform_i2c_send_byte(i2c_id, reg);
+    platform_i2c_send_byte(i2c_id, val);
+    platform_i2c_send_stop(i2c_id);
+}
+
+static int ICACHE_FLASH_ATTR l3g4200d_init(lua_State* L) {
+
+    uint32_t sda;
+    uint32_t scl;
+    uint8_t  devid;
+
+    sda = luaL_checkinteger(L, 1);
+    scl = luaL_checkinteger(L, 2);
+
+    luaL_argcheck(L, sda > 0 && scl > 0, 1, "no i2c for D0");
+
+    platform_i2c_setup(i2c_id, sda, scl, PLATFORM_I2C_SPEED_SLOW);
+    
+    devid = r8u(i2c_id, 0xF);
+
+    if (devid != 0xD3) {
+        return luaL_error(L, "device not found");
+    }
+
+    w8u(i2c_id, 0x20, 0xF);
+
+    return 0;
+}
+
+static int ICACHE_FLASH_ATTR l3g4200d_read(lua_State* L) {
+
+    uint8_t data[6];
+    int x,y,z;
+    int i;
+
+    platform_i2c_send_start(i2c_id);
+    platform_i2c_send_address(i2c_id, i2c_addr, PLATFORM_I2C_DIRECTION_TRANSMITTER);
+    platform_i2c_send_byte(i2c_id, 0xA8);
+    platform_i2c_send_start(i2c_id);
+    platform_i2c_send_address(i2c_id, i2c_addr, PLATFORM_I2C_DIRECTION_RECEIVER);
+
+    for (i=0; i<5; i++) {
+	data[i] = platform_i2c_recv_byte(i2c_id, 1);
+    }
+    
+    data[5] = platform_i2c_recv_byte(i2c_id, 0);
+
+    platform_i2c_send_stop(i2c_id);
+
+    x = (int16_t) ((data[1] << 8) | data[0]);
+    y = (int16_t) ((data[3] << 8) | data[2]);
+    z = (int16_t) ((data[5] << 8) | data[4]);
+
+    lua_pushinteger(L, x);
+    lua_pushinteger(L, y);
+    lua_pushinteger(L, z);
+
+    return 3;
+}
+
+static const LUA_REG_TYPE l3g4200d_map[] = {
+    { LSTRKEY( "read" ),         LFUNCVAL( l3g4200d_read )},
+    { LSTRKEY( "init" ),         LFUNCVAL( l3g4200d_init )},
+    { LNILKEY, LNILVAL}
+};
+
+NODEMCU_MODULE(L3G4200D, "l3g4200d", l3g4200d_map, NULL);

docs/en/modules/l3g4200d.md

@@ -0,0 +1,36 @@
+# L3G4200D Module
+| Since  | Origin / Contributor  | Maintainer  | Source  |
+| :----- | :-------------------- | :---------- | :------ |
+| 2015-04-09 | [Jason Schmidlapp](https://github.com/jschmidlapp) | [Jason Schmidlapp](https://github.com/jschmidlapp) | [l3g4200d.c](../../../app/modules/l3g4200d.c)|
+
+
+This module provides access to the [L3G4200D](http://www.st.com/web/en/resource/technical/document/datasheet/CD00265057.pdf) three axis digital gyroscope.
+
+## l3g4200d.read()
+Samples the sensor and returns the gyroscope output.
+
+#### Syntax
+`l3g4200d.read()`
+
+#### Returns
+X,Y,Z gyroscope output
+
+#### Example
+```lua
+l3g4200d.init(1, 2)
+local x,y,z = l3g4200d.read()
+print(string.format("X = %d, Y = %d, Z = %d", x, y, z)
+```
+
+## l3g4200d.init()
+Initializes the module and sets the pin configuration.
+
+#### Syntax
+`l3g4200d.init(sda, scl)`
+
+#### Parameters
+- `sda` data pin
+- `scl` clock pin
+
+#### Returns
+`nil`

mkdocs.yml

@@ -52,6 +52,7 @@ pages:
         - 'http': 'en/modules/http.md'
         - 'hx711' : 'en/modules/hx711.md'
         - 'i2c' : 'en/modules/i2c.md'
+        - 'l3g4200d' : 'en/modules/l3g4200d.md'
         - 'mdns': 'en/modules/mdns.md'
         - 'mqtt': 'en/modules/mqtt.md'
         - 'net': 'en/modules/net.md'