Merge pull request #1008 from vsky279/bme280
BME280/BMP280 Digital Pressure Sensor module
This commit is contained in:
Arnim Läuger
commit
b171ca35ba
|
|
@ -18,6 +18,7 @@
|
|||
//#define LUA_USE_MODULES_APA102
|
||||
#define LUA_USE_MODULES_BIT
|
||||
//#define LUA_USE_MODULES_BMP085
|
||||
//#define LUA_USE_MODULES_BME280
|
||||
#define LUA_USE_MODULES_CJSON
|
||||
#define LUA_USE_MODULES_COAP
|
||||
#define LUA_USE_MODULES_CRYPTO
|
||||
|
|
|
|||
|
|
@ -0,0 +1,440 @@
|
|||
// ***************************************************************************
|
||||
// BMP280 module for ESP8266 with nodeMCU
|
||||
//
|
||||
// Written by Lukas Voborsky, @voborsky
|
||||
//
|
||||
// MIT license, http://opensource.org/licenses/MIT
|
||||
// ***************************************************************************
|
||||
|
||||
//#define NODE_DEBUG
|
||||
|
||||
#include "module.h"
|
||||
#include "lauxlib.h"
|
||||
#include "platform.h"
|
||||
#include "c_math.h"
|
||||
|
||||
/****************************************************/
|
||||
/**\name registers definition */
|
||||
/***************************************************/
|
||||
#define BME280_REGISTER_CONTROL (0xF4)
|
||||
#define BME280_REGISTER_CONTROL_HUM (0xF2)
|
||||
#define BME280_REGISTER_CONFIG (0xF5)
|
||||
#define BME280_REGISTER_CHIPID (0xD0)
|
||||
#define BME280_REGISTER_VERSION (0xD1)
|
||||
#define BME280_REGISTER_SOFTRESET (0xE0)
|
||||
#define BME280_REGISTER_CAL26 (0xE1)
|
||||
#define BME280_REGISTER_TEMP (0xFA)
|
||||
#define BME280_REGISTER_PRESS (0xF7)
|
||||
#define BME280_REGISTER_HUM (0xFD)
|
||||
|
||||
#define BME280_REGISTER_DIG_T (0x88)
|
||||
#define BME280_REGISTER_DIG_P (0x8E)
|
||||
#define BME280_REGISTER_DIG_H1 (0xA1)
|
||||
#define BME280_REGISTER_DIG_H2 (0xE1)
|
||||
/****************************************************/
|
||||
/**\name I2C ADDRESS DEFINITIONS */
|
||||
/***************************************************/
|
||||
#define BME280_I2C_ADDRESS1 (0x76)
|
||||
#define BME280_I2C_ADDRESS2 (0x77)
|
||||
/****************************************************/
|
||||
/**\name POWER MODE DEFINITIONS */
|
||||
/***************************************************/
|
||||
/* Sensor Specific constants */
|
||||
#define BME280_SLEEP_MODE (0x00)
|
||||
#define BME280_FORCED_MODE (0x01)
|
||||
#define BME280_NORMAL_MODE (0x03)
|
||||
#define BME280_SOFT_RESET_CODE (0xB6)
|
||||
/****************************************************/
|
||||
/**\name OVER SAMPLING DEFINITIONS */
|
||||
/***************************************************/
|
||||
#define BME280_OVERSAMP_1X (0x01)
|
||||
#define BME280_OVERSAMP_2X (0x02)
|
||||
#define BME280_OVERSAMP_4X (0x03)
|
||||
#define BME280_OVERSAMP_8X (0x04)
|
||||
#define BME280_OVERSAMP_16X (0x05)
|
||||
/****************************************************/
|
||||
/**\name STANDBY DEFINITIONS */
|
||||
/***************************************************/
|
||||
#define BME280_STANDBY_TIME_1_MS (0x00)
|
||||
#define BME280_STANDBY_TIME_63_MS (0x01)
|
||||
#define BME280_STANDBY_TIME_125_MS (0x02)
|
||||
#define BME280_STANDBY_TIME_250_MS (0x03)
|
||||
#define BME280_STANDBY_TIME_500_MS (0x04)
|
||||
#define BME280_STANDBY_TIME_1000_MS (0x05)
|
||||
#define BME280_STANDBY_TIME_10_MS (0x06)
|
||||
#define BME280_STANDBY_TIME_20_MS (0x07)
|
||||
/****************************************************/
|
||||
/**\name FILTER DEFINITIONS */
|
||||
/***************************************************/
|
||||
#define BME280_FILTER_COEFF_OFF (0x00)
|
||||
#define BME280_FILTER_COEFF_2 (0x01)
|
||||
#define BME280_FILTER_COEFF_4 (0x02)
|
||||
#define BME280_FILTER_COEFF_8 (0x03)
|
||||
#define BME280_FILTER_COEFF_16 (0x04)
|
||||
/****************************************************/
|
||||
/**\data type definition */
|
||||
/***************************************************/
|
||||
#define BME280_S32_t int32_t
|
||||
#define BME280_U32_t uint32_t
|
||||
#define BME280_S64_t int64_t
|
||||
|
||||
#define BME280_SAMPLING_DELAY 113 //maximum measurement time in ms for maximum oversampling for all measures = 1.25 + 2.3*16 + 2.3*16 + 0.575 + 2.3*16 + 0.575 ms
|
||||
|
||||
#define r16s(reg) ((int16_t)r16u(reg))
|
||||
#define r16sLE(reg) ((int16_t)r16uLE(reg))
|
||||
|
||||
#define bme280_adc_T(void) r24u(BME280_REGISTER_TEMP)
|
||||
#define bme280_adc_P(void) r24u(BME280_REGISTER_PRESS)
|
||||
#define bme280_adc_H(void) r16u(BME280_REGISTER_HUM)
|
||||
|
||||
static const uint32_t bme280_i2c_id = 0;
|
||||
|
||||
static uint8_t bme280_i2c_addr = BME280_I2C_ADDRESS1;
|
||||
static uint8_t bme280_isbme = 0; // 1 if the chip is BME280, 0 for BMP280
|
||||
static uint8_t bme280_mode = 0; // stores oversampling settings
|
||||
os_timer_t bme280_timer; // timer for forced mode readout
|
||||
int lua_connected_readout_ref; // callback when readout is ready
|
||||
|
||||
static struct {
|
||||
uint16_t dig_T1;
|
||||
int16_t dig_T2;
|
||||
int16_t dig_T3;
|
||||
uint16_t dig_P1;
|
||||
int16_t dig_P2;
|
||||
int16_t dig_P3;
|
||||
int16_t dig_P4;
|
||||
int16_t dig_P5;
|
||||
int16_t dig_P6;
|
||||
int16_t dig_P7;
|
||||
int16_t dig_P8;
|
||||
int16_t dig_P9;
|
||||
uint8_t dig_H1;
|
||||
int16_t dig_H2;
|
||||
uint8_t dig_H3;
|
||||
int16_t dig_H4;
|
||||
int16_t dig_H5;
|
||||
int8_t dig_H6;
|
||||
} bme280_data;
|
||||
|
||||
static BME280_S32_t bme280_t_fine;
|
||||
static uint32_t bme280_h = 0;
|
||||
static double bme280_hc = 0.0;
|
||||
|
||||
static uint8_t r8u(uint8_t reg) {
|
||||
uint8_t ret;
|
||||
|
||||
platform_i2c_send_start(bme280_i2c_id);
|
||||
platform_i2c_send_address(bme280_i2c_id, bme280_i2c_addr, PLATFORM_I2C_DIRECTION_TRANSMITTER);
|
||||
platform_i2c_send_byte(bme280_i2c_id, reg);
|
||||
platform_i2c_send_stop(bme280_i2c_id);
|
||||
platform_i2c_send_start(bme280_i2c_id);
|
||||
platform_i2c_send_address(bme280_i2c_id, bme280_i2c_addr, PLATFORM_I2C_DIRECTION_RECEIVER);
|
||||
ret = platform_i2c_recv_byte(bme280_i2c_id, 0);
|
||||
platform_i2c_send_stop(bme280_i2c_id);
|
||||
//NODE_DBG("reg:%x, value:%x \n", reg, ret);
|
||||
return ret;
|
||||
}
|
||||
|
||||
static uint8_t w8u(uint8_t reg, uint8_t val) {
|
||||
platform_i2c_send_start(bme280_i2c_id);
|
||||
platform_i2c_send_address(bme280_i2c_id, bme280_i2c_addr, PLATFORM_I2C_DIRECTION_TRANSMITTER);
|
||||
platform_i2c_send_byte(bme280_i2c_id, reg);
|
||||
platform_i2c_send_byte(bme280_i2c_id, val);
|
||||
platform_i2c_send_stop(bme280_i2c_id);
|
||||
}
|
||||
|
||||
static uint16_t r16u(uint8_t reg) {
|
||||
uint8_t high = r8u(reg);
|
||||
uint8_t low = r8u(++reg);
|
||||
return (high << 8) | low;
|
||||
}
|
||||
|
||||
static uint16_t r16uLE(uint8_t reg) {
|
||||
uint8_t low = r8u(reg);
|
||||
uint8_t high = r8u(++reg);
|
||||
return (high << 8) | low;
|
||||
}
|
||||
|
||||
static uint32_t r24u(uint8_t reg) {
|
||||
uint8_t high = r8u(reg);
|
||||
uint8_t mid = r8u(++reg);
|
||||
uint8_t low = r8u(++reg);
|
||||
return (uint32_t)(((high << 16) | (mid << 8) | low) >> 4);
|
||||
}
|
||||
|
||||
// Returns temperature in DegC, resolution is 0.01 DegC. Output value of “5123” equals 51.23 DegC.
|
||||
// t_fine carries fine temperature as global value
|
||||
static BME280_S32_t bme280_compensate_T(BME280_S32_t adc_T) {
|
||||
BME280_S32_t var1, var2, T;
|
||||
var1 = ((((adc_T>>3) - ((BME280_S32_t)bme280_data.dig_T1<<1))) * ((BME280_S32_t)bme280_data.dig_T2)) >> 11;
|
||||
var2 = (((((adc_T>>4) - ((BME280_S32_t)bme280_data.dig_T1)) * ((adc_T>>4) - ((BME280_S32_t)bme280_data.dig_T1))) >> 12) *
|
||||
((BME280_S32_t)bme280_data.dig_T3)) >> 14;
|
||||
bme280_t_fine = var1 + var2;
|
||||
T = (bme280_t_fine * 5 + 128) >> 8;
|
||||
return T;
|
||||
}
|
||||
|
||||
// Returns pressure in Pa as unsigned 32 bit integer in Q24.8 format (24 integer bits and 8 fractional bits).
|
||||
// Output value of “24674867” represents 24674867/256 = 96386.2 Pa = 963.862 hPa
|
||||
static BME280_U32_t bme280_compensate_P(BME280_S32_t adc_P) {
|
||||
BME280_S64_t var1, var2, p;
|
||||
var1 = ((BME280_S64_t)bme280_t_fine) - 128000;
|
||||
var2 = var1 * var1 * (BME280_S64_t)bme280_data.dig_P6;
|
||||
var2 = var2 + ((var1*(BME280_S64_t)bme280_data.dig_P5)<<17);
|
||||
var2 = var2 + (((BME280_S64_t)bme280_data.dig_P4)<<35);
|
||||
var1 = ((var1 * var1 * (BME280_S64_t)bme280_data.dig_P3)>>8) + ((var1 * (BME280_S64_t)bme280_data.dig_P2)<<12);
|
||||
var1 = (((((BME280_S64_t)1)<<47)+var1))*((BME280_S64_t)bme280_data.dig_P1)>>33;
|
||||
if (var1 == 0) {
|
||||
return 0; // avoid exception caused by division by zero
|
||||
}
|
||||
p = 1048576-adc_P;
|
||||
p = (((p<<31)-var2)*3125)/var1;
|
||||
var1 = (((BME280_S64_t)bme280_data.dig_P9) * (p>>13) * (p>>13)) >> 25;
|
||||
var2 = (((BME280_S64_t)bme280_data.dig_P8) * p) >> 19;
|
||||
p = ((p + var1 + var2) >> 8) + (((BME280_S64_t)bme280_data.dig_P7)<<4);
|
||||
p = (p * 10) >> 8;
|
||||
return (BME280_U32_t)p;
|
||||
}
|
||||
|
||||
// Returns humidity in %RH as unsigned 32 bit integer in Q22.10 format (22 integer and 10 fractional bits).
|
||||
// Output value of “47445” represents 47445/1024 = 46.333 %RH
|
||||
static BME280_U32_t bme280_compensate_H(BME280_S32_t adc_H) {
|
||||
BME280_S32_t v_x1_u32r;
|
||||
|
||||
v_x1_u32r = (bme280_t_fine - ((BME280_S32_t)76800));
|
||||
v_x1_u32r = (((((adc_H << 14) - (((BME280_S32_t)bme280_data.dig_H4) << 20) - (((BME280_S32_t)bme280_data.dig_H5) * v_x1_u32r)) +
|
||||
((BME280_S32_t)16384)) >> 15) * (((((((v_x1_u32r * ((BME280_S32_t)bme280_data.dig_H6)) >> 10) * (((v_x1_u32r *
|
||||
((BME280_S32_t)bme280_data.dig_H3)) >> 11) + ((BME280_S32_t)32768))) >> 10) + ((BME280_S32_t)2097152)) *
|
||||
((BME280_S32_t)bme280_data.dig_H2) + 8192) >> 14));
|
||||
v_x1_u32r = (v_x1_u32r - (((((v_x1_u32r >> 15) * (v_x1_u32r >> 15)) >> 7) * ((BME280_S32_t)bme280_data.dig_H1)) >> 4));
|
||||
v_x1_u32r = (v_x1_u32r < 0 ? 0 : v_x1_u32r);
|
||||
v_x1_u32r = (v_x1_u32r > 419430400 ? 419430400 : v_x1_u32r);
|
||||
v_x1_u32r = v_x1_u32r>>12;
|
||||
return (BME280_U32_t)((v_x1_u32r * 1000)>>10);
|
||||
}
|
||||
|
||||
static int bme280_lua_init(lua_State* L) {
|
||||
uint8_t sda;
|
||||
uint8_t scl;
|
||||
uint8_t ossh;
|
||||
uint8_t config;
|
||||
uint8_t ack;
|
||||
|
||||
uint8_t const bit3 = 0b111;
|
||||
uint8_t const bit2 = 0b11;
|
||||
|
||||
if (!lua_isnumber(L, 1) || !lua_isnumber(L, 2)) {
|
||||
return luaL_error(L, "wrong arg range");
|
||||
}
|
||||
sda = luaL_checkinteger(L, 1);
|
||||
scl = luaL_checkinteger(L, 2);
|
||||
|
||||
bme280_mode = (!lua_isnumber(L, 6)?BME280_NORMAL_MODE:(luaL_checkinteger(L, 6)&bit2)) // 6-th parameter: power mode
|
||||
| ((!lua_isnumber(L, 4)?BME280_OVERSAMP_16X:(luaL_checkinteger(L, 4)&bit3)) << 2) // 4-th parameter: pressure oversampling
|
||||
| ((!lua_isnumber(L, 3)?BME280_OVERSAMP_16X:(luaL_checkinteger(L, 3)&bit3)) << 5); // 3-rd parameter: temperature oversampling
|
||||
|
||||
ossh = (!lua_isnumber(L, 5))?BME280_OVERSAMP_16X:(luaL_checkinteger(L, 5)&bit3); // 5-th parameter: humidity oversampling
|
||||
|
||||
config = ((!lua_isnumber(L, 7)?BME280_STANDBY_TIME_20_MS:(luaL_checkinteger(L, 7)&bit3))<< 4) // 7-th parameter: inactive duration in normal mode
|
||||
| ((!lua_isnumber(L, 8)?BME280_FILTER_COEFF_16:(luaL_checkinteger(L, 8)&bit3)) << 1); // 8-th parameter: IIR filter
|
||||
NODE_DBG("mode: %x\nhumidity oss: %x\nconfig: %x\n", bme280_mode, ossh, config);
|
||||
|
||||
platform_i2c_setup(bme280_i2c_id, sda, scl, PLATFORM_I2C_SPEED_SLOW);
|
||||
|
||||
bme280_i2c_addr = BME280_I2C_ADDRESS1;
|
||||
platform_i2c_send_start(bme280_i2c_id);
|
||||
ack = platform_i2c_send_address(bme280_i2c_id, bme280_i2c_addr, PLATFORM_I2C_DIRECTION_TRANSMITTER);
|
||||
platform_i2c_send_stop(bme280_i2c_id);
|
||||
if (!ack) {
|
||||
NODE_DBG("No ACK on address: %x\n", bme280_i2c_addr);
|
||||
bme280_i2c_addr = BME280_I2C_ADDRESS2;
|
||||
platform_i2c_send_start(bme280_i2c_id);
|
||||
ack = platform_i2c_send_address(bme280_i2c_id, bme280_i2c_addr, PLATFORM_I2C_DIRECTION_TRANSMITTER);
|
||||
platform_i2c_send_stop(bme280_i2c_id);
|
||||
if (!ack) {
|
||||
NODE_DBG("No ACK on address: %x\n", bme280_i2c_addr);
|
||||
return 0;
|
||||
}
|
||||
}
|
||||
|
||||
uint8_t chipid = r8u(BME280_REGISTER_CHIPID);
|
||||
NODE_DBG("chip_id: %x\n", chipid);
|
||||
bme280_isbme = (chipid == 0x60);
|
||||
|
||||
uint8_t reg = BME280_REGISTER_DIG_T;
|
||||
bme280_data.dig_T1 = r16uLE(reg); reg+=2;
|
||||
bme280_data.dig_T2 = r16sLE(reg); reg+=2;
|
||||
bme280_data.dig_T3 = r16sLE(reg);
|
||||
//NODE_DBG("dig_T: %d\t%d\t%d\n", bme280_data.dig_T1, bme280_data.dig_T2, bme280_data.dig_T3);
|
||||
|
||||
reg = BME280_REGISTER_DIG_P;
|
||||
bme280_data.dig_P1 = r16uLE(reg); reg+=2;
|
||||
bme280_data.dig_P2 = r16sLE(reg); reg+=2;
|
||||
bme280_data.dig_P3 = r16sLE(reg); reg+=2;
|
||||
bme280_data.dig_P4 = r16sLE(reg); reg+=2;
|
||||
bme280_data.dig_P5 = r16sLE(reg); reg+=2;
|
||||
bme280_data.dig_P6 = r16sLE(reg); reg+=2;
|
||||
bme280_data.dig_P7 = r16sLE(reg); reg+=2;
|
||||
bme280_data.dig_P8 = r16sLE(reg); reg+=2;
|
||||
bme280_data.dig_P9 = r16sLE(reg);
|
||||
// NODE_DBG("dig_P: %d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\t%d\n", bme280_data.dig_P1, bme280_data.dig_P2, bme280_data.dig_P3, bme280_data.dig_P4, bme280_data.dig_P5, bme280_data.dig_P6, bme280_data.dig_P7, bme280_data.dig_P8, bme280_data.dig_P9);
|
||||
|
||||
w8u(BME280_REGISTER_CONFIG, config);
|
||||
if (bme280_isbme) {
|
||||
reg = BME280_REGISTER_DIG_H1;
|
||||
bme280_data.dig_H1 = r8u(reg);
|
||||
reg = BME280_REGISTER_DIG_H2;
|
||||
bme280_data.dig_H2 = r16sLE(reg); reg+=2;
|
||||
bme280_data.dig_H3 = r8u(reg); reg++;
|
||||
bme280_data.dig_H4 = ((int16_t)r8u(reg) << 4 | (r8u(reg+1) & 0xF)); reg+=2;
|
||||
bme280_data.dig_H5 = ((int16_t)r8u(reg+1) << 4 | (r8u(reg) >> 4)); reg+=2;
|
||||
bme280_data.dig_H6 = (int8_t)r8u(reg);
|
||||
// NODE_DBG("dig_H: %d\t%d\t%d\t%d\t%d\t%d\n", bme280_data.dig_H1, bme280_data.dig_H2, bme280_data.dig_H3, bme280_data.dig_H4, bme280_data.dig_H5, bme280_data.dig_H6);
|
||||
|
||||
w8u(BME280_REGISTER_CONTROL_HUM, ossh);
|
||||
lua_pushinteger(L, 2);
|
||||
} else {
|
||||
lua_pushinteger(L, 1);
|
||||
}
|
||||
w8u(BME280_REGISTER_CONTROL, bme280_mode);
|
||||
|
||||
return 1;
|
||||
}
|
||||
|
||||
static void bme280_readoutdone (void *arg)
|
||||
{
|
||||
NODE_DBG("timer out\n");
|
||||
lua_State *L = arg;
|
||||
lua_rawgeti (L, LUA_REGISTRYINDEX, lua_connected_readout_ref);
|
||||
lua_call (L, 0, 0);
|
||||
luaL_unref (L, LUA_REGISTRYINDEX, lua_connected_readout_ref);
|
||||
os_timer_disarm (&bme280_timer);
|
||||
}
|
||||
|
||||
static int bme280_lua_startreadout(lua_State* L) {
|
||||
uint32_t delay;
|
||||
|
||||
if (lua_isnumber(L, 1)) {
|
||||
delay = luaL_checkinteger(L, 1);
|
||||
if (!delay) {delay = BME280_SAMPLING_DELAY;} // if delay is 0 then set the default delay
|
||||
}
|
||||
|
||||
if (!lua_isnoneornil(L, 2)) {
|
||||
lua_pushvalue(L, 2);
|
||||
lua_connected_readout_ref = luaL_ref(L, LUA_REGISTRYINDEX);
|
||||
} else {
|
||||
lua_connected_readout_ref = LUA_NOREF;
|
||||
}
|
||||
|
||||
w8u(BME280_REGISTER_CONTROL, (bme280_mode & 0xFC) | BME280_FORCED_MODE);
|
||||
NODE_DBG("control old: %x, control: %x, delay: %d\n", bme280_mode, (bme280_mode & 0xFC) | BME280_FORCED_MODE, delay);
|
||||
|
||||
if (lua_connected_readout_ref != LUA_NOREF) {
|
||||
NODE_DBG("timer armed\n");
|
||||
os_timer_disarm (&bme280_timer);
|
||||
os_timer_setfn (&bme280_timer, (os_timer_func_t *)bme280_readoutdone, L);
|
||||
os_timer_arm (&bme280_timer, delay, 0); // trigger callback when readout is ready
|
||||
}
|
||||
return 0;
|
||||
}
|
||||
|
||||
static int bme280_lua_temp(lua_State* L) {
|
||||
uint32_t adc_T = bme280_adc_T();
|
||||
if (adc_T ==0x80000) return 0;
|
||||
lua_pushinteger(L, bme280_compensate_T(adc_T));
|
||||
lua_pushinteger(L, bme280_t_fine);
|
||||
return 2;
|
||||
}
|
||||
|
||||
static int bme280_lua_baro(lua_State* L) {
|
||||
uint32_t adc_T = bme280_adc_T();
|
||||
uint32_t T = bme280_compensate_T(adc_T);
|
||||
uint32_t adc_P = bme280_adc_P();
|
||||
if (adc_P ==0x80000 || adc_T == 0x80000)
|
||||
return 0;
|
||||
lua_pushinteger(L, bme280_compensate_P(adc_P));
|
||||
lua_pushinteger(L, T);
|
||||
return 2;
|
||||
}
|
||||
|
||||
static int bme280_lua_humi(lua_State* L) {
|
||||
if (!bme280_isbme) return 0;
|
||||
uint32_t adc_T = bme280_adc_T();
|
||||
uint32_t T = bme280_compensate_T(adc_T);
|
||||
uint32_t adc_H = bme280_adc_H();
|
||||
if (adc_T == 0x80000)
|
||||
return 0;
|
||||
lua_pushinteger(L, bme280_compensate_H(adc_H));
|
||||
lua_pushinteger(L, T);
|
||||
return 2;
|
||||
}
|
||||
|
||||
static int bme280_lua_qfe2qnh(lua_State* L) {
|
||||
if (!lua_isnumber(L, 2)) {
|
||||
return luaL_error(L, "wrong arg range");
|
||||
}
|
||||
int32_t qfe = luaL_checkinteger(L, 1);
|
||||
int32_t h = luaL_checkinteger(L, 2);
|
||||
|
||||
double hc;
|
||||
if (bme280_h == h) {
|
||||
hc = bme280_hc;
|
||||
} else {
|
||||
hc = pow((double)(1.0 - 2.25577e-5 * h), (double)(-5.25588));
|
||||
bme280_hc = hc; bme280_h = h;
|
||||
}
|
||||
double qnh = (double)qfe * hc;
|
||||
lua_pushinteger(L, (int32_t)(qnh + 0.5));
|
||||
return 1;
|
||||
}
|
||||
|
||||
static int bme280_lua_altitude(lua_State* L) {
|
||||
if (!lua_isnumber(L, 2)) {
|
||||
return luaL_error(L, "wrong arg range");
|
||||
}
|
||||
int32_t P = luaL_checkinteger(L, 1);
|
||||
int32_t qnh = luaL_checkinteger(L, 2);
|
||||
|
||||
double h = (1.0 - pow((double)P/(double)qnh, 1.0/5.25588)) / 2.25577e-5 * 100.0;
|
||||
lua_pushinteger(L, (int32_t)(h + (((h<0)?-1:(h>0)) * 0.5)));
|
||||
return 1;
|
||||
}
|
||||
|
||||
static double ln(double x) {
|
||||
double y = (x-1)/(x+1);
|
||||
double y2 = y*y;
|
||||
double r = 0;
|
||||
for (int8_t i=33; i>0; i-=2) { //we've got the power
|
||||
r = 1.0/(double)i + y2 * r;
|
||||
}
|
||||
return 2*y*r;
|
||||
}
|
||||
|
||||
static int bme280_lua_dewpoint(lua_State* L) {
|
||||
const double c243 = 243.5;
|
||||
const double c17 = 17.67;
|
||||
if (!lua_isnumber(L, 2)) {
|
||||
return luaL_error(L, "wrong arg range");
|
||||
}
|
||||
double H = luaL_checkinteger(L, 1)/100000.0;
|
||||
double T = luaL_checkinteger(L, 2)/100.0;
|
||||
|
||||
double c = ln(H) + ((c17 * T) / (c243 + T));
|
||||
double d = (c243 * c)/(c17 - c) * 100.0;
|
||||
lua_pushinteger(L, (int32_t)(d + (((d<0)?-1:(d>0)) * 0.5)));
|
||||
return 1;
|
||||
}
|
||||
|
||||
static const LUA_REG_TYPE bme280_map[] = {
|
||||
{ LSTRKEY( "init" ), LFUNCVAL(bme280_lua_init)},
|
||||
{ LSTRKEY( "temp" ), LFUNCVAL(bme280_lua_temp)},
|
||||
{ LSTRKEY( "baro" ), LFUNCVAL(bme280_lua_baro)},
|
||||
{ LSTRKEY( "humi" ), LFUNCVAL(bme280_lua_humi)},
|
||||
{ LSTRKEY( "startreadout" ), LFUNCVAL(bme280_lua_startreadout)},
|
||||
{ LSTRKEY( "qfe2qnh" ), LFUNCVAL(bme280_lua_qfe2qnh)},
|
||||
{ LSTRKEY( "altitude" ), LFUNCVAL(bme280_lua_altitude)},
|
||||
{ LSTRKEY( "dewpoint" ), LFUNCVAL(bme280_lua_dewpoint)},
|
||||
{ LNILKEY, LNILVAL}
|
||||
};
|
||||
|
||||
NODEMCU_MODULE(BME280, "bme280", bme280_map, NULL);
|
||||
|
|
@ -0,0 +1,225 @@
|
|||
# bme280 module
|
||||
|
||||
The bme280 module provides simple interface to BME280/BMP280 temperature/air presssure/humidity sensor.
|
||||
|
||||
|Method|Description|
|
||||
|---------------|-------------|
|
||||
|[init()](#init)|Initializes the module and sets the pin configuration.|
|
||||
|[temp()](#temp)|Reads the sensor and returns the temperature in celsius as an integer multiplied with 100.|
|
||||
|[baro()](#baro)|Reads the sensor and returns the air temperature in hectopascals as an integer multiplied with 1000.|
|
||||
|[humi()](#humi)|Reads the sensor and returns the air relative humidity in percents as an integer multiplied with 100.|
|
||||
|[startreadout()](#startreadout)|Starts readout (turns the sensor into forced mode).|
|
||||
|[qfe2qnh()](#qfe2qnh)|For given altitude converts the air pressure to sea level air pressure.|
|
||||
|[altitude()](#altitude)|For given air pressure and sea level air pressure returns the altitude in meters as an integer multiplied with 100.|
|
||||
|[dewpoint()](#dewpoint)|For given temperature and relative humidity returns the dew point in celsius as an integer multiplied with 100.|
|
||||
|
||||
## Methods
|
||||
|
||||
###init()
|
||||
|
||||
####Description
|
||||
Initialize module. Initialization is mandatory before read values.
|
||||
|
||||
####Syntax
|
||||
`init(sda, scl)`
|
||||
|
||||
`init(sda, scl, temp_oss, press_oss, humi_oss, power_mode, inactive_duration, IIR_filter)`
|
||||
|
||||
####Parameters
|
||||
* `sda` - SDA pin
|
||||
* `scl` - SCL pin
|
||||
* (optional) `temp_oss` - Controls oversampling of temperature data. Default oversampling is 16x.
|
||||
* (optional) `press_oss` - Controls oversampling of pressure data. Default oversampling is 16x.
|
||||
* (optional) `humi_oss` - Controls oversampling of humidity data. Default oversampling is 16x
|
||||
* (optional) `sensor_mode` - Controls the sensor mode of the device. Default sensor more is normal.
|
||||
* (optional) `inactive_duration` - Controls inactive duration in normal mode. Default inactive duration is 20ms.
|
||||
* (optional) `IIR_filter` - Controls the time constant of the IIR filter. Default fitler coefficient is 16.
|
||||
|
||||
|`temp_oss`, `press_oss`, `humi_oss`|Data oversampling|
|
||||
|-----|-----------------|
|
||||
|0|Skipped (output set to 0x80000)|
|
||||
|1|oversampling ×1|
|
||||
|2|oversampling ×2|
|
||||
|3|oversampling ×4|
|
||||
|4|oversampling ×8|
|
||||
|**5**|**oversampling ×16**|
|
||||
|
||||
|`sensor_mode`|Sensor mode|
|
||||
|-----|-----------------|
|
||||
|0|Sleep mode|
|
||||
|1 and 2|Forced mode|
|
||||
|**3**|**Normal mode**|
|
||||
|
||||
Using forced mode is recommended for applications which require low sampling rate or hostbased synchronization. The sensor enters into sleep mode after a forced readout. Please refer to BME280 Final Datasheet for more details.
|
||||
|
||||
|`inactive_duration`|t standby (ms)|
|
||||
|-----|-----------------|
|
||||
|0|0.5|
|
||||
|1|62.5|
|
||||
|2|125|
|
||||
|3|250|
|
||||
|4|500|
|
||||
|5|1000|
|
||||
|6|10|
|
||||
|**7**|**20**|
|
||||
|
||||
|`IIR_filter`|Filter coefficient |
|
||||
|-----|-----------------|
|
||||
|0|Filter off|
|
||||
|1|2|
|
||||
|2|4|
|
||||
|3|8|
|
||||
|**4**|**16**|
|
||||
|
||||
####Returns
|
||||
`nil` initialization has failed (no sensor connected?), `2` sensor is BME280, `1` sensor is BMP280
|
||||
|
||||
### Example
|
||||
```lua
|
||||
alt=320 -- altitude of the measurement place
|
||||
|
||||
bme280.init(3, 4)
|
||||
|
||||
P, T = bme280.baro()
|
||||
print(string.format("QFE=%d.%03d", P/1000, P%1000))
|
||||
|
||||
-- convert measure air pressure to sea level pressure
|
||||
QNH = bme280.qfe2qnh(P, alt)
|
||||
print(string.format("QNH=%d.%03d", QNH/1000, QNH%1000))
|
||||
|
||||
H, T = bme280.humi()
|
||||
print(string.format("T=%d.%02d", T/100, T%100))
|
||||
print(string.format("humidity=%d.%03d%%", H/1000, H%1000))
|
||||
D = bme280.dewpoint(H, T)
|
||||
print(string.format("dew_point=%d.%02d", D/100, D%100))
|
||||
|
||||
-- altimeter function - calculate altitude based on current sea level pressure (QNH) and measure pressure
|
||||
P = bme280.baro()
|
||||
curAlt = bme280.altitude(P, QNH)
|
||||
print(string.format("altitude=%d.%02d", curAlt/100, curAlt%100))
|
||||
```
|
||||
Use `bme280.init(sda, scl, 1, 3, 0, 3, 0, 4)` for "game mode" - Oversampling settings pressure ×4, temperature ×1, humidity ×0, sensor mode: normal mode, inactive duration = 0.5 ms, IIR filter settings filter coefficient 16.
|
||||
|
||||
Example of readout in forced mode (asynchronous)
|
||||
```lua
|
||||
bme280.init(3, 4, nil, nil, nil, 0) -- initialize to sleep mode
|
||||
bme280.startreadout(0, function ()
|
||||
T = bme280.temp()
|
||||
print(string.format("T=%d.%02d", T/100, T%100))
|
||||
end)
|
||||
```
|
||||
|
||||
**-** [Back to index](#index)
|
||||
|
||||
###temp()
|
||||
####Description
|
||||
Reads the sensor and returns the temperature in celsius as an integer multiplied with 100.
|
||||
|
||||
####Syntax
|
||||
`temp()`
|
||||
|
||||
####Parameters
|
||||
none
|
||||
|
||||
####Returns
|
||||
* `T` - temperature in celsius as an integer multiplied with 100 or `nil` when readout is not successful.
|
||||
* `t_fine` - temperature measure used in pressure and humidity compensation formulas (generally no need to use this value)
|
||||
|
||||
**-** [Back to index](#index)
|
||||
|
||||
###baro()
|
||||
####Description
|
||||
Reads the sensor and returns the air temperature in hectopascals as an integer multiplied with 1000 or `nil` when readout is not successful.
|
||||
Current temperature is needed to calculate the air pressure so temperature reading is performed prior reading pressure data. Second returned variable is therefore current temperature.
|
||||
|
||||
####Syntax
|
||||
`baro()`
|
||||
|
||||
####Parameters
|
||||
none
|
||||
|
||||
####Returns
|
||||
* `P` - air pressure in hectopascals multiplied by 1000.
|
||||
* `T` - temperature in celsius as an integer multiplied with 100.
|
||||
|
||||
**-** [Back to index](#index)
|
||||
|
||||
###humi()
|
||||
####Description
|
||||
Reads the sensor and returns the air relative humidity in percents as an integer multiplied with 100 or `nil` when readout is not successful.
|
||||
Current temperature is needed to calculate the relative humidity so temperature reading is performed prior reading pressure data. Second returned variable is therefore current temperature.
|
||||
|
||||
####Syntax
|
||||
`humi()`
|
||||
|
||||
####Parameters
|
||||
none
|
||||
|
||||
####Returns
|
||||
* `H` - last relative humidity reading in % times 1000.
|
||||
* `T` - temperature in celsius as an integer multiplied with 100.
|
||||
|
||||
**-** [Back to index](#index)
|
||||
|
||||
###startreadout()
|
||||
Starts readout (turns the sensor into forced mode). After the readout the sensor turns to sleep mode.
|
||||
|
||||
####Syntax
|
||||
`startreadout(delay, callback)`
|
||||
|
||||
####Parameters
|
||||
* `delay` - sets sensor to forced mode and calls the `callback` (if provided) after given number of milliseconds. For 0 the default delay is set to 113ms (sufficient time to perform reading for oversampling settings 16x). For different oversampling setting please refer to BME280 Final Datasheet - Appendix B: Measurement time and current calculation.
|
||||
* `callback` - if provided it will be invoked after given `delay`. The sensor reading should be finalized by then so.
|
||||
|
||||
####Returns
|
||||
`nil`
|
||||
|
||||
**-** [Back to index](#index)
|
||||
|
||||
###qfe2qnh()
|
||||
Description
|
||||
For given altitude converts the air pressure to sea level air pressure.
|
||||
|
||||
####Syntax
|
||||
`qfe2qnh(P, altitude)`
|
||||
|
||||
####Parameters
|
||||
* `P` - measured pressure
|
||||
* `altitude` - altitude in meters of measurement point
|
||||
|
||||
####Returns
|
||||
* `QNH` - sea level pressure
|
||||
|
||||
**-** [Back to index](#index)
|
||||
|
||||
###altitude()
|
||||
####Description
|
||||
For given air pressure and sea level air pressure returns the altitude in meters as an integer multiplied with 100, i.e. altimeter function.
|
||||
|
||||
####Syntax
|
||||
`altitude(P, QNH)`
|
||||
|
||||
####Parameters
|
||||
* `P` - measured pressure
|
||||
* `QNH` - current sea level pressure
|
||||
|
||||
####Returns
|
||||
* `altitude` - altitude in meters of measurement point
|
||||
|
||||
**-** [Back to index](#index)
|
||||
|
||||
###dewpoint()
|
||||
####Description
|
||||
For given temperature and relative humidity returns the dew point in celsius as an integer multiplied with 100.
|
||||
|
||||
####Syntax
|
||||
`dewpoint(H, T)`
|
||||
|
||||
####Parameters
|
||||
* `H` - relative humidity in percent multiplied by 1000.
|
||||
* `T` - temperate in celsius multiplied by 100.
|
||||
|
||||
####Returns
|
||||
* `dewpoint` - dew point in celsisus.
|
||||
|
||||
**-** [Back to index](#index)
|
||||
Loading…
Reference in New Issue