|
| 1 | +// *************************************************************************** |
| 2 | +// BMP280 module for ESP8266 with nodeMCU |
| 3 | +// |
| 4 | +// Written by Lukas Voborsky, @voborsky |
| 5 | +// |
| 6 | +// MIT license, http://opensource.org/licenses/MIT |
| 7 | +// *************************************************************************** |
| 8 | + |
| 9 | +// #define NODE_DEBUG |
| 10 | + |
| 11 | +#include "module.h" |
| 12 | +#include "lauxlib.h" |
| 13 | +#include "platform.h" |
| 14 | +#include "user_interface.h" |
| 15 | +#include <math.h> |
| 16 | + |
| 17 | +/****************************************************/ |
| 18 | +/**\name registers definition */ |
| 19 | +/***************************************************/ |
| 20 | +#define BME280_REGISTER_CONTROL (0xF4) |
| 21 | +#define BME280_REGISTER_CONTROL_HUM (0xF2) |
| 22 | +#define BME280_REGISTER_CONFIG (0xF5) |
| 23 | +#define BME280_REGISTER_CHIPID (0xD0) |
| 24 | +#define BME280_REGISTER_VERSION (0xD1) |
| 25 | +#define BME280_REGISTER_SOFTRESET (0xE0) |
| 26 | +#define BME280_REGISTER_CAL26 (0xE1) |
| 27 | +#define BME280_REGISTER_PRESS (0xF7) // 0xF7-0xF9 |
| 28 | +#define BME280_REGISTER_TEMP (0xFA) // 0xFA-0xFC |
| 29 | +#define BME280_REGISTER_HUM (0xFD) // 0xFD-0xFE |
| 30 | + |
| 31 | +#define BME280_REGISTER_DIG_T (0x88) // 0x88-0x8D ( 6) |
| 32 | +#define BME280_REGISTER_DIG_P (0x8E) // 0x8E-0x9F (18) |
| 33 | +#define BME280_REGISTER_DIG_H1 (0xA1) // 0xA1 ( 1) |
| 34 | +#define BME280_REGISTER_DIG_H2 (0xE1) // 0xE1-0xE7 ( 7) |
| 35 | +/****************************************************/ |
| 36 | +/**\name I2C ADDRESS DEFINITIONS */ |
| 37 | +/***************************************************/ |
| 38 | +#define BME280_I2C_ADDRESS1 (0x76) |
| 39 | +#define BME280_I2C_ADDRESS2 (0x77) |
| 40 | +/****************************************************/ |
| 41 | +/**\name POWER MODE DEFINITIONS */ |
| 42 | +/***************************************************/ |
| 43 | +/* Sensor Specific constants */ |
| 44 | +#define BME280_SLEEP_MODE (0x00) |
| 45 | +#define BME280_FORCED_MODE (0x01) |
| 46 | +#define BME280_NORMAL_MODE (0x03) |
| 47 | +#define BME280_SOFT_RESET_CODE (0xB6) |
| 48 | +/****************************************************/ |
| 49 | +/**\name OVER SAMPLING DEFINITIONS */ |
| 50 | +/***************************************************/ |
| 51 | +#define BME280_OVERSAMP_1X (0x01) |
| 52 | +#define BME280_OVERSAMP_2X (0x02) |
| 53 | +#define BME280_OVERSAMP_4X (0x03) |
| 54 | +#define BME280_OVERSAMP_8X (0x04) |
| 55 | +#define BME280_OVERSAMP_16X (0x05) |
| 56 | +/****************************************************/ |
| 57 | +/**\name STANDBY TIME DEFINITIONS */ |
| 58 | +/***************************************************/ |
| 59 | +#define BME280_STANDBY_TIME_1_MS (0x00) |
| 60 | +#define BME280_STANDBY_TIME_63_MS (0x01) |
| 61 | +#define BME280_STANDBY_TIME_125_MS (0x02) |
| 62 | +#define BME280_STANDBY_TIME_250_MS (0x03) |
| 63 | +#define BME280_STANDBY_TIME_500_MS (0x04) |
| 64 | +#define BME280_STANDBY_TIME_1000_MS (0x05) |
| 65 | +#define BME280_STANDBY_TIME_10_MS (0x06) |
| 66 | +#define BME280_STANDBY_TIME_20_MS (0x07) |
| 67 | +/****************************************************/ |
| 68 | +/**\name FILTER DEFINITIONS */ |
| 69 | +/***************************************************/ |
| 70 | +#define BME280_FILTER_COEFF_OFF (0x00) |
| 71 | +#define BME280_FILTER_COEFF_2 (0x01) |
| 72 | +#define BME280_FILTER_COEFF_4 (0x02) |
| 73 | +#define BME280_FILTER_COEFF_8 (0x03) |
| 74 | +#define BME280_FILTER_COEFF_16 (0x04) |
| 75 | +/****************************************************/ |
| 76 | +/**\data type definition */ |
| 77 | +/***************************************************/ |
| 78 | +#define BME280_S32_t int32_t |
| 79 | +#define BME280_U32_t uint32_t |
| 80 | +#define BME280_S64_t int64_t |
| 81 | + |
| 82 | +#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 |
| 83 | + |
| 84 | +// #define r16s(reg) ((int16_t)r16u(reg)) |
| 85 | +// #define r16sLE(reg) ((int16_t)r16uLE(reg)) |
| 86 | + |
| 87 | +// #define bme280_adc_P(void) r24u(BME280_REGISTER_PRESS) |
| 88 | +// #define bme280_adc_T(void) r24u(BME280_REGISTER_TEMP) |
| 89 | +// #define bme280_adc_H(void) r16u(BME280_REGISTER_HUM) |
| 90 | + |
| 91 | +typedef struct { |
| 92 | + uint16_t dig_T1; |
| 93 | + int16_t dig_T2; |
| 94 | + int16_t dig_T3; |
| 95 | + uint16_t dig_P1; |
| 96 | + int16_t dig_P2; |
| 97 | + int16_t dig_P3; |
| 98 | + int16_t dig_P4; |
| 99 | + int16_t dig_P5; |
| 100 | + int16_t dig_P6; |
| 101 | + int16_t dig_P7; |
| 102 | + int16_t dig_P8; |
| 103 | + int16_t dig_P9; |
| 104 | + uint8_t dig_H1; |
| 105 | + int16_t dig_H2; |
| 106 | + uint8_t dig_H3; |
| 107 | + int16_t dig_H4; |
| 108 | + int16_t dig_H5; |
| 109 | + int8_t dig_H6; |
| 110 | +} bme280_data_t; |
| 111 | +typedef bme280_data_t* bme280_data_p; |
| 112 | +bme280_data_p bme280_data; |
| 113 | + |
| 114 | + |
| 115 | +BME280_S32_t bme280_t_fine; |
| 116 | + |
| 117 | +// Returns temperature in DegC, resolution is 0.01 DegC. Output value of “5123” equals 51.23 DegC. |
| 118 | +// t_fine carries fine temperature as global value |
| 119 | +BME280_S32_t bme280_compensate_T(BME280_S32_t adc_T) { |
| 120 | + BME280_S32_t var1, var2, T; |
| 121 | + var1 = ((((adc_T>>3) - ((BME280_S32_t)(*bme280_data).dig_T1<<1))) * ((BME280_S32_t)(*bme280_data).dig_T2)) >> 11; |
| 122 | + var2 = (((((adc_T>>4) - ((BME280_S32_t)(*bme280_data).dig_T1)) * ((adc_T>>4) - ((BME280_S32_t)(*bme280_data).dig_T1))) >> 12) * |
| 123 | + ((BME280_S32_t)(*bme280_data).dig_T3)) >> 14; |
| 124 | + bme280_t_fine = var1 + var2; |
| 125 | + T = (bme280_t_fine * 5 + 128) >> 8; |
| 126 | + return T; |
| 127 | +} |
| 128 | + |
| 129 | +// Returns pressure in Pa as unsigned 32 bit integer in Q24.8 format (24 integer bits and 8 fractional bits). |
| 130 | +// Output value of “24674867” represents 24674867/256 = 96386.2 Pa = 963.862 hPa |
| 131 | +BME280_U32_t bme280_compensate_P(BME280_S32_t adc_P) { |
| 132 | + BME280_S64_t var1, var2, p; |
| 133 | + var1 = ((BME280_S64_t)bme280_t_fine) - 128000; |
| 134 | + var2 = var1 * var1 * (BME280_S64_t)(*bme280_data).dig_P6; |
| 135 | + var2 = var2 + ((var1*(BME280_S64_t)(*bme280_data).dig_P5)<<17); |
| 136 | + var2 = var2 + (((BME280_S64_t)(*bme280_data).dig_P4)<<35); |
| 137 | + var1 = ((var1 * var1 * (BME280_S64_t)(*bme280_data).dig_P3)>>8) + ((var1 * (BME280_S64_t)(*bme280_data).dig_P2)<<12); |
| 138 | + var1 = (((((BME280_S64_t)1)<<47)+var1))*((BME280_S64_t)(*bme280_data).dig_P1)>>33; |
| 139 | + if (var1 == 0) { |
| 140 | + return 0; // avoid exception caused by division by zero |
| 141 | + } |
| 142 | + p = 1048576-adc_P; |
| 143 | + p = (((p<<31)-var2)*3125)/var1; |
| 144 | + var1 = (((BME280_S64_t)(*bme280_data).dig_P9) * (p>>13) * (p>>13)) >> 25; |
| 145 | + var2 = (((BME280_S64_t)(*bme280_data).dig_P8) * p) >> 19; |
| 146 | + p = ((p + var1 + var2) >> 8) + (((BME280_S64_t)(*bme280_data).dig_P7)<<4); |
| 147 | + p = (p * 10) >> 8; |
| 148 | + return (BME280_U32_t)p; |
| 149 | +} |
| 150 | + |
| 151 | +// Returns humidity in %RH as unsigned 32 bit integer in Q22.10 format (22 integer and 10 fractional bits). |
| 152 | +// Output value of “47445” represents 47445/1024 = 46.333 %RH |
| 153 | +BME280_U32_t bme280_compensate_H(BME280_S32_t adc_H) { |
| 154 | + BME280_S32_t v_x1_u32r; |
| 155 | + |
| 156 | + v_x1_u32r = (bme280_t_fine - ((BME280_S32_t)76800)); |
| 157 | + v_x1_u32r = (((((adc_H << 14) - (((BME280_S32_t)(*bme280_data).dig_H4) << 20) - (((BME280_S32_t)(*bme280_data).dig_H5) * v_x1_u32r)) + |
| 158 | + ((BME280_S32_t)16384)) >> 15) * (((((((v_x1_u32r * ((BME280_S32_t)(*bme280_data).dig_H6)) >> 10) * (((v_x1_u32r * |
| 159 | + ((BME280_S32_t)(*bme280_data).dig_H3)) >> 11) + ((BME280_S32_t)32768))) >> 10) + ((BME280_S32_t)2097152)) * |
| 160 | + ((BME280_S32_t)(*bme280_data).dig_H2) + 8192) >> 14)); |
| 161 | + v_x1_u32r = (v_x1_u32r - (((((v_x1_u32r >> 15) * (v_x1_u32r >> 15)) >> 7) * ((BME280_S32_t)(*bme280_data).dig_H1)) >> 4)); |
| 162 | + v_x1_u32r = (v_x1_u32r < 0 ? 0 : v_x1_u32r); |
| 163 | + v_x1_u32r = (v_x1_u32r > 419430400 ? 419430400 : v_x1_u32r); |
| 164 | + v_x1_u32r = v_x1_u32r>>12; |
| 165 | + return (BME280_U32_t)((v_x1_u32r * 1000)>>10); |
| 166 | +} |
| 167 | + |
| 168 | +double ln(double x) { |
| 169 | + double y = (x-1)/(x+1); |
| 170 | + double y2 = y*y; |
| 171 | + double r = 0; |
| 172 | + for (int8_t i=33; i>0; i-=2) { //we've got the power |
| 173 | + r = 1.0/(double)i + y2 * r; |
| 174 | + } |
| 175 | + return 2*y*r; |
| 176 | +} |
| 177 | + |
| 178 | +uint32_t bme280_h = 0; // buffer last qfe2qnh calculation |
| 179 | +double bme280_hc = 1.0; |
| 180 | + |
| 181 | +double bme280_qfe2qnh(double qfe, double h) { |
| 182 | + double hc; |
| 183 | + if (bme280_h == h) { |
| 184 | + hc = bme280_hc; |
| 185 | + } else { |
| 186 | + hc = pow((double)(1.0 - 2.25577e-5 * h), (double)(-5.25588)); |
| 187 | + bme280_hc = hc; bme280_h = h; |
| 188 | + } |
| 189 | + double qnh = (double)qfe * hc; |
| 190 | + return qnh; |
| 191 | +} |
| 192 | + |
| 193 | +int bme280_lua_setup(lua_State* L) { |
| 194 | + uint8_t bme280_mode = 0; // stores oversampling settings |
| 195 | + uint8_t bme280_ossh = 0; // stores humidity oversampling settings |
| 196 | + uint8_t config; |
| 197 | + |
| 198 | + uint8_t const bit3 = 0b111; |
| 199 | + uint8_t const bit2 = 0b11; |
| 200 | + |
| 201 | + bme280_mode = (!lua_isnumber(L, 5)?BME280_NORMAL_MODE:(luaL_checkinteger(L, 5)&bit2)) // 4-th parameter: power mode |
| 202 | + | ((!lua_isnumber(L, 3)?BME280_OVERSAMP_16X:(luaL_checkinteger(L, 3)&bit3)) << 2) // 2-nd parameter: pressure oversampling |
| 203 | + | ((!lua_isnumber(L, 2)?BME280_OVERSAMP_16X:(luaL_checkinteger(L, 2)&bit3)) << 5); // 1-st parameter: temperature oversampling |
| 204 | + |
| 205 | + bme280_ossh = (!lua_isnumber(L, 4))?BME280_OVERSAMP_16X:(luaL_checkinteger(L, 4)&bit3); // 3-rd parameter: humidity oversampling |
| 206 | + |
| 207 | + config = ((!lua_isnumber(L, 6)?BME280_STANDBY_TIME_20_MS:(luaL_checkinteger(L, 6)&bit3))<< 5) // 5-th parameter: inactive duration in normal mode |
| 208 | + | ((!lua_isnumber(L, 7)?BME280_FILTER_COEFF_16:(luaL_checkinteger(L, 7)&bit3)) << 2); // 6-th parameter: IIR filter |
| 209 | + // NODE_DBG("mode: %x\nhumidity oss: %x\nconfig: %x\n", bme280_mode, bme280_ossh, config); |
| 210 | + |
| 211 | +#define r16uLE_buf(reg) (uint16_t)((reg[1] << 8) | reg[0]) |
| 212 | +#define r16sLE_buf(reg) (int16_t)(r16uLE_buf(reg)) |
| 213 | + size_t reg_len; |
| 214 | + const char *buf = luaL_checklstring(L, 1, ®_len); |
| 215 | + |
| 216 | + bme280_data = (bme280_data_p) memset(lua_newuserdata(L, sizeof(*bme280_data)), 0, sizeof(*bme280_data)); // first parameter to be returned |
| 217 | + const uint8_t *reg; |
| 218 | + |
| 219 | + reg = buf; |
| 220 | + (*bme280_data).dig_T1 = r16uLE_buf(reg); reg+=2; |
| 221 | + (*bme280_data).dig_T2 = r16sLE_buf(reg); reg+=2; |
| 222 | + (*bme280_data).dig_T3 = r16sLE_buf(reg); reg+=2; |
| 223 | + // NODE_DBG("dig_T: %d\t%d\t%d\n", (*bme280_data).dig_T1, (*bme280_data).dig_T2, (*bme280_data).dig_T3); |
| 224 | + |
| 225 | + (*bme280_data).dig_P1 = r16uLE_buf(reg); reg+=2; |
| 226 | + (*bme280_data).dig_P2 = r16sLE_buf(reg); reg+=2; |
| 227 | + (*bme280_data).dig_P3 = r16sLE_buf(reg); reg+=2; |
| 228 | + (*bme280_data).dig_P4 = r16sLE_buf(reg); reg+=2; |
| 229 | + (*bme280_data).dig_P5 = r16sLE_buf(reg); reg+=2; |
| 230 | + (*bme280_data).dig_P6 = r16sLE_buf(reg); reg+=2; |
| 231 | + (*bme280_data).dig_P7 = r16sLE_buf(reg); reg+=2; |
| 232 | + (*bme280_data).dig_P8 = r16sLE_buf(reg); reg+=2; |
| 233 | + (*bme280_data).dig_P9 = r16sLE_buf(reg); reg+=2; |
| 234 | + // 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); |
| 235 | + |
| 236 | + if (reg_len>=6+18) { // is BME? |
| 237 | + (*bme280_data).dig_H1 = (uint8)reg[0]; reg+=1; |
| 238 | + (*bme280_data).dig_H2 = r16sLE_buf(reg); reg+=2; |
| 239 | + (*bme280_data).dig_H3 = reg[0]; reg++; |
| 240 | + (*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 |
| 241 | + (*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 |
| 242 | + (*bme280_data).dig_H6 = (int8_t)reg[0]; |
| 243 | + 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); |
| 244 | + } |
| 245 | +#undef r16uLE_buf |
| 246 | +#undef r16sLE_buf |
| 247 | + |
| 248 | + int i = 1; |
| 249 | + char cfg[2]={'\0', '\0'}; |
| 250 | + lua_createtable(L, 3, 0); /* configuration table */ |
| 251 | + cfg[0]=(char)config; |
| 252 | + lua_pushstring(L, cfg); |
| 253 | + lua_rawseti(L, -2, i++); |
| 254 | + cfg[0]=(char)bme280_ossh; |
| 255 | + lua_pushstring(L, cfg); |
| 256 | + lua_rawseti(L, -2, i++); |
| 257 | + cfg[0]=(char)bme280_mode; |
| 258 | + lua_pushstring(L, cfg); |
| 259 | + lua_rawseti(L, -2, i); |
| 260 | + return 2; |
| 261 | +} |
| 262 | + |
| 263 | +// Return T, QFE, H if no altitude given |
| 264 | +// Return T, QFE, H, QNH if altitude given |
| 265 | +int bme280_lua_read(lua_State* L) { |
| 266 | + double qfe; |
| 267 | + |
| 268 | + bme280_data = (bme280_data_p)lua_touserdata(L, 1); |
| 269 | + |
| 270 | + size_t reg_len; |
| 271 | + const char *buf = luaL_checklstring(L, 2, ®_len); // registers are P[3], T[3], H[2] |
| 272 | + |
| 273 | + if (reg_len != 8 && reg_len !=6) { |
| 274 | + luaL_error(L, "invalid readout data"); |
| 275 | + } |
| 276 | + |
| 277 | + uint8_t calc_qnh = lua_isnumber(L, 3); |
| 278 | + |
| 279 | + // Must do Temp first since bme280_t_fine is used by the other compensation functions |
| 280 | + uint32_t adc_T = (uint32_t)(((buf[3] << 16) | (buf[4] << 8) | buf[5]) >> 4); |
| 281 | + if (adc_T == 0x80000 || adc_T == 0xfffff) |
| 282 | + return 0; |
| 283 | + lua_pushnumber(L, bme280_compensate_T(adc_T)/100.0); |
| 284 | + |
| 285 | + uint32_t adc_P = (uint32_t)(((buf[0] << 16) | (buf[1] << 8) | buf[2]) >> 4); |
| 286 | + NODE_DBG("adc_P: %d\n", adc_P); |
| 287 | + if (adc_P ==0x80000 || adc_P == 0xfffff) { |
| 288 | + lua_pushnil(L); |
| 289 | + calc_qnh = 0; |
| 290 | + } else { |
| 291 | + qfe = bme280_compensate_P(adc_P)/1000.0; |
| 292 | + lua_pushnumber (L, qfe); |
| 293 | + } |
| 294 | + |
| 295 | + uint32_t adc_H = (uint32_t)((buf[6] << 8) | buf[7]); |
| 296 | + if (reg_len!=8 || adc_H == 0x8000 || adc_H == 0xffff) |
| 297 | + lua_pushnil(L); |
| 298 | + else |
| 299 | + lua_pushnumber (L, bme280_compensate_H(adc_H)/1000.0); |
| 300 | + |
| 301 | + if (calc_qnh) { // have altitude |
| 302 | + int32_t h = luaL_checknumber(L, 3); |
| 303 | + double qnh = bme280_qfe2qnh(qfe, h); |
| 304 | + lua_pushnumber (L, qnh); |
| 305 | + return 4; |
| 306 | + } |
| 307 | + return 3; |
| 308 | +} |
| 309 | + |
| 310 | +int bme280_lua_qfe2qnh(lua_State* L) { |
| 311 | + if (lua_isuserdata(L, 1) || lua_istable(L, 1)) { // allow to call it as object method, userdata have no use here |
| 312 | + lua_remove(L, 1); |
| 313 | + } |
| 314 | + double qfe = luaL_checknumber(L, 1); |
| 315 | + double h = luaL_checknumber(L, 2); |
| 316 | + double qnh = bme280_qfe2qnh(qfe, h); |
| 317 | + lua_pushnumber(L, qnh); |
| 318 | + return 1; |
| 319 | +} |
| 320 | + |
| 321 | +int bme280_lua_altitude(lua_State* L) { |
| 322 | + if (lua_isuserdata(L, 1) || lua_istable(L, 1)) { // allow to call it as object method, userdata have no use here |
| 323 | + lua_remove(L, 1); |
| 324 | + } |
| 325 | + double P = luaL_checknumber(L, 1); |
| 326 | + double qnh = luaL_checknumber(L, 2); |
| 327 | + double h = (1.0 - pow((double)P/(double)qnh, 1.0/5.25588)) / 2.25577e-5; |
| 328 | + lua_pushnumber (L, h); |
| 329 | + return 1; |
| 330 | +} |
| 331 | + |
| 332 | +int bme280_lua_dewpoint(lua_State* L) { |
| 333 | + if (lua_isuserdata(L, 1) || lua_istable(L, 1)) { // allow to call it as object method, userdata have no use here |
| 334 | + lua_remove(L, 1); |
| 335 | + } |
| 336 | + double H = luaL_checknumber(L, 1)/100.0; // percent |
| 337 | + double T = luaL_checknumber(L, 2); |
| 338 | + |
| 339 | + const double c243 = 243.5; |
| 340 | + const double c17 = 17.67; |
| 341 | + double c = ln(H) + ((c17 * T) / (c243 + T)); |
| 342 | + double d = (c243 * c)/(c17 - c); |
| 343 | + |
| 344 | + lua_pushnumber (L, d); |
| 345 | + return 1; |
| 346 | +} |
| 347 | + |
| 348 | +LROT_BEGIN(bme280_math, NULL, 0) |
| 349 | + LROT_FUNCENTRY( setup, bme280_lua_setup ) |
| 350 | + LROT_FUNCENTRY( read, bme280_lua_read ) |
| 351 | + LROT_FUNCENTRY( qfe2qnh, bme280_lua_qfe2qnh ) |
| 352 | + LROT_FUNCENTRY( altitude, bme280_lua_altitude ) |
| 353 | + LROT_FUNCENTRY( dewpoint, bme280_lua_dewpoint ) |
| 354 | +LROT_END(bme280_math, NULL, 0) |
| 355 | + |
| 356 | + |
| 357 | +NODEMCU_MODULE(BME280_MATH, "bme280_math", bme280_math, NULL); |
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