// *************************************************************************** // 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 "user_interface.h" #include /****************************************************/ /**\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_PRESS (0xF7) // 0xF7-0xF9 #define BME280_REGISTER_TEMP (0xFA) // 0xFA-0xFC #define BME280_REGISTER_HUM (0xFD) // 0xFD-0xFE #define BME280_REGISTER_DIG_T (0x88) // 0x88-0x8D ( 6) #define BME280_REGISTER_DIG_P (0x8E) // 0x8E-0x9F (18) #define BME280_REGISTER_DIG_H1 (0xA1) // 0xA1 ( 1) #define BME280_REGISTER_DIG_H2 (0xE1) // 0xE1-0xE7 ( 7) /****************************************************/ /**\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 TIME 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_P(void) r24u(BME280_REGISTER_PRESS) // #define bme280_adc_T(void) r24u(BME280_REGISTER_TEMP) // #define bme280_adc_H(void) r16u(BME280_REGISTER_HUM) typedef 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_t; typedef bme280_data_t* bme280_data_p; bme280_data_p bme280_data; BME280_S32_t bme280_t_fine; // 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 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 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 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); } 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; } uint32_t bme280_h = 0; // buffer last qfe2qnh calculation double bme280_hc = 1.0; double bme280_qfe2qnh(double qfe, double h) { 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; return qnh; } int bme280_lua_setup(lua_State* L) { uint8_t bme280_mode = 0; // stores oversampling settings uint8_t bme280_ossh = 0; // stores humidity oversampling settings uint8_t config; uint8_t const bit3 = 0b111; uint8_t const bit2 = 0b11; bme280_mode = (!lua_isnumber(L, 5)?BME280_NORMAL_MODE:(luaL_checkinteger(L, 5)&bit2)) // 4-th parameter: power mode | ((!lua_isnumber(L, 3)?BME280_OVERSAMP_16X:(luaL_checkinteger(L, 3)&bit3)) << 2) // 2-nd parameter: pressure oversampling | ((!lua_isnumber(L, 2)?BME280_OVERSAMP_16X:(luaL_checkinteger(L, 2)&bit3)) << 5); // 1-st parameter: temperature oversampling bme280_ossh = (!lua_isnumber(L, 4))?BME280_OVERSAMP_16X:(luaL_checkinteger(L, 4)&bit3); // 3-rd parameter: humidity oversampling config = ((!lua_isnumber(L, 6)?BME280_STANDBY_TIME_20_MS:(luaL_checkinteger(L, 6)&bit3))<< 5) // 5-th parameter: inactive duration in normal mode | ((!lua_isnumber(L, 7)?BME280_FILTER_COEFF_16:(luaL_checkinteger(L, 7)&bit3)) << 2); // 6-th parameter: IIR filter // NODE_DBG("mode: %x\nhumidity oss: %x\nconfig: %x\n", bme280_mode, bme280_ossh, config); #define r16uLE_buf(reg) (uint16_t)((reg[1] << 8) | reg[0]) #define r16sLE_buf(reg) (int16_t)(r16uLE_buf(reg)) size_t reg_len; const char *buf = luaL_checklstring(L, 1, ®_len); bme280_data = (bme280_data_p) memset(lua_newuserdata(L, sizeof(*bme280_data)), 0, sizeof(*bme280_data)); // first parameter to be returned const uint8_t *reg; reg = buf; (*bme280_data).dig_T1 = r16uLE_buf(reg); reg+=2; (*bme280_data).dig_T2 = r16sLE_buf(reg); reg+=2; (*bme280_data).dig_T3 = r16sLE_buf(reg); reg+=2; // NODE_DBG("dig_T: %d\t%d\t%d\n", (*bme280_data).dig_T1, (*bme280_data).dig_T2, (*bme280_data).dig_T3); (*bme280_data).dig_P1 = r16uLE_buf(reg); reg+=2; (*bme280_data).dig_P2 = r16sLE_buf(reg); reg+=2; (*bme280_data).dig_P3 = r16sLE_buf(reg); reg+=2; (*bme280_data).dig_P4 = r16sLE_buf(reg); reg+=2; (*bme280_data).dig_P5 = r16sLE_buf(reg); reg+=2; (*bme280_data).dig_P6 = r16sLE_buf(reg); reg+=2; (*bme280_data).dig_P7 = r16sLE_buf(reg); reg+=2; (*bme280_data).dig_P8 = r16sLE_buf(reg); reg+=2; (*bme280_data).dig_P9 = r16sLE_buf(reg); reg+=2; // 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); if (reg_len>=6+18) { // is BME? (*bme280_data).dig_H1 = (uint8)reg[0]; reg+=1; (*bme280_data).dig_H2 = r16sLE_buf(reg); reg+=2; (*bme280_data).dig_H3 = reg[0]; reg++; (*bme280_data).dig_H4 = (int16_t)reg[0] << 4 | (reg[1] & 0x0F); reg+=1; // H4[11:4 3:0] = 0xE4[7:0] 0xE5[3:0] 12-bit signed (*bme280_data).dig_H5 = (int16_t)reg[1] << 4 | (reg[0] >> 4); reg+=2; // H5[11:4 3:0] = 0xE6[7:0] 0xE5[7:4] 12-bit signed (*bme280_data).dig_H6 = (int8_t)reg[0]; 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); } #undef r16uLE_buf #undef r16sLE_buf int i = 1; char cfg[2]={'\0', '\0'}; lua_createtable(L, 3, 0); /* configuration table */ cfg[0]=(char)config; lua_pushstring(L, cfg); lua_rawseti(L, -2, i++); cfg[0]=(char)bme280_ossh; lua_pushstring(L, cfg); lua_rawseti(L, -2, i++); cfg[0]=(char)bme280_mode; lua_pushstring(L, cfg); lua_rawseti(L, -2, i); return 2; } // Return T, QFE, H if no altitude given // Return T, QFE, H, QNH if altitude given int bme280_lua_read(lua_State* L) { double qfe; bme280_data = (bme280_data_p)lua_touserdata(L, 1); size_t reg_len; const char *buf = luaL_checklstring(L, 2, ®_len); // registers are P[3], T[3], H[2] if (reg_len != 8 && reg_len !=6) { luaL_error(L, "invalid readout data"); } uint8_t calc_qnh = lua_isnumber(L, 3); // Must do Temp first since bme280_t_fine is used by the other compensation functions uint32_t adc_T = (uint32_t)(((buf[3] << 16) | (buf[4] << 8) | buf[5]) >> 4); if (adc_T == 0x80000 || adc_T == 0xfffff) return 0; lua_pushnumber(L, bme280_compensate_T(adc_T)/100.0); uint32_t adc_P = (uint32_t)(((buf[0] << 16) | (buf[1] << 8) | buf[2]) >> 4); NODE_DBG("adc_P: %d\n", adc_P); if (adc_P ==0x80000 || adc_P == 0xfffff) { lua_pushnil(L); calc_qnh = 0; } else { qfe = bme280_compensate_P(adc_P)/1000.0; lua_pushnumber (L, qfe); } uint32_t adc_H = (uint32_t)((buf[6] << 8) | buf[7]); if (reg_len!=8 || adc_H == 0x8000 || adc_H == 0xffff) lua_pushnil(L); else lua_pushnumber (L, bme280_compensate_H(adc_H)/1000.0); if (calc_qnh) { // have altitude int32_t h = luaL_checknumber(L, 3); double qnh = bme280_qfe2qnh(qfe, h); lua_pushnumber (L, qnh); return 4; } return 3; } int bme280_lua_qfe2qnh(lua_State* L) { if (lua_isuserdata(L, 1) || lua_istable(L, 1)) { // allow to call it as object method, userdata have no use here lua_remove(L, 1); } double qfe = luaL_checknumber(L, 1); double h = luaL_checknumber(L, 2); double qnh = bme280_qfe2qnh(qfe, h); lua_pushnumber(L, qnh); return 1; } int bme280_lua_altitude(lua_State* L) { if (lua_isuserdata(L, 1) || lua_istable(L, 1)) { // allow to call it as object method, userdata have no use here lua_remove(L, 1); } double P = luaL_checknumber(L, 1); double qnh = luaL_checknumber(L, 2); double h = (1.0 - pow((double)P/(double)qnh, 1.0/5.25588)) / 2.25577e-5; lua_pushnumber (L, h); return 1; } int bme280_lua_dewpoint(lua_State* L) { if (lua_isuserdata(L, 1) || lua_istable(L, 1)) { // allow to call it as object method, userdata have no use here lua_remove(L, 1); } double H = luaL_checknumber(L, 1)/100.0; // percent double T = luaL_checknumber(L, 2); const double c243 = 243.5; const double c17 = 17.67; double c = ln(H) + ((c17 * T) / (c243 + T)); double d = (c243 * c)/(c17 - c); lua_pushnumber (L, d); return 1; } LROT_BEGIN(bme280_math, NULL, 0) LROT_FUNCENTRY( setup, bme280_lua_setup ) LROT_FUNCENTRY( read, bme280_lua_read ) LROT_FUNCENTRY( qfe2qnh, bme280_lua_qfe2qnh ) LROT_FUNCENTRY( altitude, bme280_lua_altitude ) LROT_FUNCENTRY( dewpoint, bme280_lua_dewpoint ) LROT_END(bme280_math, NULL, 0) NODEMCU_MODULE(BME280_MATH, "bme280_math", bme280_math, NULL);