nodemcu-firmware/app/modules/hdc1080.c

109 lines
3.0 KiB
C

/*
* Driver for TI Texas Instruments HDC1080 Temperature/Humidity Sensor.
* Code By Metin KOC
* Sixfab Inc. metin@sixfab.com
* Code based on ADXL345 driver.
*/
#include "module.h"
#include "lauxlib.h"
#include "platform.h"
#include "c_stdlib.h"
#include "c_string.h"
#include "c_math.h"
static const uint32_t hdc1080_i2c_id = 0;
static const uint8_t hdc1080_i2c_addr = 0x40;
#define HDC1080_TEMPERATURE_REGISTER 0X00
#define HDC1080_HUMIDITY_REGISTER 0X01
#define HDC1080_CONFIG_REGISTER 0X02
static int hdc1080_setup(lua_State* L) {
// Configure Sensor
platform_i2c_send_start(hdc1080_i2c_id);
platform_i2c_send_address(hdc1080_i2c_id, hdc1080_i2c_addr, PLATFORM_I2C_DIRECTION_TRANSMITTER);
platform_i2c_send_byte(hdc1080_i2c_id, HDC1080_CONFIG_REGISTER);
platform_i2c_send_byte(hdc1080_i2c_id, 0x05); //Bit[10] to 1 for 11 bit resolution , Set Bit[9:8] to 01 for 11 bit resolution.
platform_i2c_send_byte(hdc1080_i2c_id, 0x00);
platform_i2c_send_stop(hdc1080_i2c_id);
return 0;
}
static int hdc1080_read(lua_State* L) {
uint8_t data[2];
#ifdef LUA_NUMBER_INTEGRAL
int temp;
int humidity;
#else
float temp;
float humidity;
#endif
int i;
platform_i2c_send_start(hdc1080_i2c_id);
platform_i2c_send_address(hdc1080_i2c_id, hdc1080_i2c_addr, PLATFORM_I2C_DIRECTION_TRANSMITTER);
platform_i2c_send_byte(hdc1080_i2c_id, HDC1080_TEMPERATURE_REGISTER);
platform_i2c_send_stop(hdc1080_i2c_id);
os_delay_us(7000);
platform_i2c_send_start(hdc1080_i2c_id);
platform_i2c_send_address(hdc1080_i2c_id, hdc1080_i2c_addr, PLATFORM_I2C_DIRECTION_RECEIVER);
for (i=0; i<2; i++) {
data[i] = platform_i2c_recv_byte(hdc1080_i2c_id, 1);
}
platform_i2c_send_stop(hdc1080_i2c_id);
#ifdef LUA_NUMBER_INTEGRAL
temp = ((((data[0]<<8)|data[1])*165)>>16)-40;
lua_pushinteger(L, (int)temp);
#else
temp = ((float)((data[0]<<8)|data[1])/(float)pow(2,16))*165.0f-40.0f;
lua_pushnumber(L, temp);
#endif
platform_i2c_send_start(hdc1080_i2c_id);
platform_i2c_send_address(hdc1080_i2c_id, hdc1080_i2c_addr, PLATFORM_I2C_DIRECTION_TRANSMITTER);
platform_i2c_send_byte(hdc1080_i2c_id, HDC1080_HUMIDITY_REGISTER);
platform_i2c_send_stop(hdc1080_i2c_id);
os_delay_us(7000);
platform_i2c_send_start(hdc1080_i2c_id);
platform_i2c_send_address(hdc1080_i2c_id, hdc1080_i2c_addr, PLATFORM_I2C_DIRECTION_RECEIVER);
for (i=0; i<2; i++) {
data[i] = platform_i2c_recv_byte(hdc1080_i2c_id, 1);
}
platform_i2c_send_stop(hdc1080_i2c_id);
#ifdef LUA_NUMBER_INTEGRAL
humidity = ((((data[0]<<8)|data[1]))*100)>>16;
lua_pushinteger(L, (int)humidity);
#else
humidity = ((float)((data[0]<<8)|data[1])/(float)pow(2,16))*100.0f;
lua_pushnumber(L, humidity);
#endif
return 2;
}
static const LUA_REG_TYPE hdc1080_map[] = {
{ LSTRKEY( "read" ), LFUNCVAL( hdc1080_read )},
{ LSTRKEY( "setup" ), LFUNCVAL( hdc1080_setup )},
{ LNILKEY, LNILVAL}
};
NODEMCU_MODULE(HDC1080, "hdc1080", hdc1080_map, NULL);