/*
xsns_92_scd40.ino - SCD40/SCD41 I2C CO2(+temp+RH) sensor support for Tasmota,
based on frogmore42's xsns_42_scd30.ino
Copyright (C) 2021 Frogmore42, Arnold-n
This program is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
This program is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with this program. If not, see .
*/
// define USE_SCD40 to use SCD40 or SCD41 device; use SCD41-functions only if you use SCD41 sensor
// define USE_SCD40_LOWPOWER to use low-power periodic measurement mode (both SCD40 and SCD41)
// define SCD40_DEBUG to debug
// Console instructions supported: (errorvalue=-1 in case of error, errorvalue=0 otherwise)
// (data=-1 in case of error, value otherwise)
// (third colum: time in ms needed for execution)
// (DPM: may be executed during periodic measurements)
//
// Instruction Returns Exec(ms) DPM Function
// ------------------------------------------------------------------------------------
// SCD40Alt data 1 no get Sensor Altitude (in m)
// SCD40Alt x errorvalue 1 no set Sensor Altitude (in m)
// SCD40Auto data 1 no get CalibrationEnabled status (bool)
// SCD40Auto x errorvalue 1 no set CalibrationEnabled status (bool)
// SCD40Toff data 1 no get Temperature offset (centigrades)
// SCD40Toff x errorvalue 1 no set Temperature offset (centigrades) (some rounding may occur)
// SCD40Pres x errorvalue 1 yes set Ambient Pressure (mbar) (overrides Sensor Altitude setting)
// SCD40Cal x errorvalue 400 no perform forced recalibration (ppm CO2)
// SCD40Test errorvalue 10000 no perform selftest
// SCD40StLp errorvalue 0 no start periodic measurement in low-power mode (1/30s)
// SCD40Strt errorvalue 0 no start periodic measurement (1/5s)
// SCD40Stop errorvalue 500 yes stop periodic measurement
// SCD40Pers errorvalue 800 no persist settings in EEPROM (2000 write cycles guaranteed)
// SCD40Rein errorvalue 20 no reinit sensor
// SCD40Fact errorvalue 1200 no factory reset sensor
//
// SCD40Sing errorvalue 5000 no (SCD41 only) measure single shot
// SCD40SRHT errorvalue 50 no (SCD41 only) measure single shot, RHT only
//#define SCD40_DEBUG
#ifdef USE_I2C
#ifdef USE_SCD40
#define XSNS_92 92
#define XI2C_62 62 // See I2CDEVICES.md
// #define SCD40_ADDRESS 0x62 // already defined in lib
#define SCD40_MAX_MISSED_READS 30 // in seconds (at 1 read/second)
#define SCD40_STATE_NO_ERROR 0
#define SCD40_STATE_ERROR_DATA_CRC 1
#define SCD40_STATE_ERROR_READ_MEAS 2
#define SCD40_STATE_ERROR_SOFT_RESET 3
#define SCD40_STATE_ERROR_I2C_RESET 4
#include "Arduino.h"
#include
#define D_CMND_SCD40 "SCD40"
const char S_JSON_SCD40_COMMAND_NVALUE[] PROGMEM = "{\"" D_CMND_SCD40 "%s\":%d}";
//const char S_JSON_SCD40_COMMAND[] PROGMEM = "{\"" D_CMND_SCD40 "%s\"}";
const char kSCD40_Commands[] PROGMEM = "Alt|Auto|Toff|Pres|Cal|Test|StLP|Strt|Stop|Pers|Rein|Fact|Sing|SRHT";
/*********************************************************************************************\
* enumerations
\*********************************************************************************************/
enum SCD40_Commands { // commands useable in console or rules
CMND_SCD40_ALTITUDE,
CMND_SCD40_AUTOMODE,
CMND_SCD40_TEMPOFFSET,
CMND_SCD40_PRESSURE,
CMND_SCD40_FORCEDRECALIBRATION,
CMND_SCD40_SELFTEST,
CMND_SCD40_START_MEASUREMENT_LOW_POWER,
CMND_SCD40_START_MEASUREMENT,
CMND_SCD40_STOP_MEASUREMENT,
CMND_SCD40_PERSIST,
CMND_SCD40_REINIT,
CMND_SCD40_FACTORYRESET,
CMND_SCD40_SINGLESHOT,
CMND_SCD40_SINGLESHOT_RHT_ONLY
};
FrogmoreScd40 scd40;
bool scd40Found = false;
bool scd40IsDataValid = false;
int scd40ErrorState = SCD40_STATE_NO_ERROR;
int scd40Loop_count = 0;
int scd40DataNotAvailable_count = 0;
int scd40GoodMeas_count = 0;
int scd40Reset_count = 0;
int scd40CrcError_count = 0;
int scd40i2cReset_count = 0;
uint16_t scd40_CO2 = 0;
uint16_t scd40_CO2EAvg = 0;
float scd40_Humid = 0.0;
float scd40_Temp = 0.0;
void Scd40Detect(void)
{
if (!I2cSetDevice(SCD40_ADDRESS)) { return; }
scd40.begin();
// don't stop in case of error, try to continue
delay(10); // not sure whether this is needed
int error = scd40.forceStopPeriodicMeasurement(); // after reboot, stop (if any) periodic measurement, or reinit may not work
#ifdef SCD40_DEBUG
AddLog(LOG_LEVEL_DEBUG, PSTR("SCD40 force-stop error: %d"), error);
#endif
delay(550); // wait >500ms after stopPeriodicMeasurement before SCD40 allows any other command
error = scd40.reinit(); // just in case
#ifdef SCD40_DEBUG
AddLog(LOG_LEVEL_DEBUG, PSTR("SCD40 reinit error: %d"), error);
#endif
delay(20); // not sure whether this is needed
uint16_t sn[3];
error = scd40.getSerialNumber(sn);
AddLog(LOG_LEVEL_INFO, PSTR("SCD40 serial nr 0x%X 0x%X 0x%X") ,sn[0], sn[1], sn[2]);
// by default, start measurements, only register device if this succeeds
#ifdef USE_SCD40_LOWPOWER
if (scd40.startLowPowerPeriodicMeasurement()) { return; }
#else
if (scd40.startPeriodicMeasurement()) { return; }
#endif
I2cSetActiveFound(SCD40_ADDRESS, "SCD40");
scd40Found = true;
#ifdef SCD40_DEBUG
AddLog(LOG_LEVEL_DEBUG, PSTR("SCD40 found, measurements started."));
#endif
}
// gets data from the sensor
void Scd40Update(void)
{
bool isAvailable;
scd40Loop_count++;
uint32_t error = 0;
switch (scd40ErrorState) {
case SCD40_STATE_NO_ERROR: {
error = scd40.readMeasurement(&scd40_CO2, &scd40_CO2EAvg, &scd40_Temp, &scd40_Humid);
switch (error) {
case ERROR_SCD40_NO_ERROR:
scd40Loop_count = 0;
scd40IsDataValid = true;
scd40GoodMeas_count++;
#ifdef USE_LIGHT
LightSetSignal(CO2_LOW, CO2_HIGH, scd40_CO2);
#endif // USE_LIGHT
break;
case ERROR_SCD40_NO_DATA:
scd40DataNotAvailable_count++;
AddLog(LOG_LEVEL_DEBUG, PSTR("SCD40: no data available."));
break;
case ERROR_SCD40_CRC_ERROR:
scd40CrcError_count++;
#ifdef SCD40_DEBUG
AddLog(LOG_LEVEL_ERROR, PSTR("SCD40: CRC error, CRC error: %ld, good: %ld, no data: %ld, sc30_reset: %ld, i2c_reset: %ld"),
scd40CrcError_count, scd40GoodMeas_count, scd40DataNotAvailable_count, scd40Reset_count, scd40i2cReset_count);
#endif
break;
default: {
scd40ErrorState = SCD40_STATE_ERROR_READ_MEAS;
#ifdef SCD40_DEBUG
AddLog(LOG_LEVEL_ERROR, PSTR("SCD40: Update: ReadMeasurement error: 0x%lX, counter: %ld"), error, scd40Loop_count);
#endif
return;
}
break;
}
}
break;
case SCD40_STATE_ERROR_READ_MEAS: {
#ifdef SCD40_DEBUG
AddLog(LOG_LEVEL_ERROR, PSTR("SCD40: (rd) in error state: %d, good: %ld, no data: %ld, sc30 reset: %ld, i2c reset: %ld"),
scd40ErrorState, scd40GoodMeas_count, scd40DataNotAvailable_count, scd40Reset_count, scd40i2cReset_count);
AddLog(LOG_LEVEL_ERROR, PSTR("SCD40: not answering, sending soft reset, counter: %ld"), scd40Loop_count);
#endif
scd40Reset_count++;
error = scd40.stopPeriodicMeasurement();
if (error) {
scd40ErrorState = SCD40_STATE_ERROR_SOFT_RESET;
#ifdef SCD40_DEBUG
AddLog(LOG_LEVEL_ERROR, PSTR("SCD40: stopPeriodicMeasurement got error: 0x%lX"), error);
#endif
} else {
error = scd40.reinit();
if (error) {
#ifdef SCD40_DEBUG
AddLog(LOG_LEVEL_ERROR, PSTR("SCD40: resetting got error: 0x%lX"), error);
#endif
scd40ErrorState = SCD40_STATE_ERROR_SOFT_RESET;
} else {
scd40ErrorState = ERROR_SCD40_NO_ERROR;
}
}
}
break;
case SCD40_STATE_ERROR_SOFT_RESET: {
#ifdef SCD40_DEBUG
AddLog(LOG_LEVEL_ERROR, PSTR("SCD40: (rst) in error state: %d, good: %ld, no data: %ld, sc30 reset: %ld, i2c reset: %ld"),
scd40ErrorState, scd40GoodMeas_count, scd40DataNotAvailable_count, scd40Reset_count, scd40i2cReset_count);
AddLog(LOG_LEVEL_ERROR, PSTR("SCD40: clearing i2c bus"));
#endif
scd40i2cReset_count++;
error = scd40.clearI2CBus();
if (error) {
scd40ErrorState = SCD40_STATE_ERROR_I2C_RESET;
#ifdef SCD40_DEBUG
AddLog(LOG_LEVEL_ERROR, PSTR("SCD40: error clearing i2c bus: 0x%lX"), error);
#endif
} else {
scd40ErrorState = ERROR_SCD40_NO_ERROR;
}
}
break;
case SCD40_STATE_ERROR_I2C_RESET: {
// Give up
}
break;
}
if (scd40Loop_count > SCD40_MAX_MISSED_READS) {
AddLog(LOG_LEVEL_DEBUG, PSTR("SCD40: max-missed-reads."));
scd40IsDataValid = false;
}
}
int Scd40GetCommand(int command_code, uint16_t *pvalue)
{
switch (command_code)
{
case CMND_SCD40_ALTITUDE:
return scd40.getSensorAltitude(pvalue);
break;
case CMND_SCD40_AUTOMODE:
return scd40.getAutomaticSelfCalibrationEnabled(pvalue);
break;
case CMND_SCD40_TEMPOFFSET:
return scd40.getTemperatureOffset(pvalue);
break;
case CMND_SCD40_SELFTEST:
return scd40.performSelfTest(pvalue);
break;
default:
// else for Unknown command
break;
}
return 0; // Fix GCC 10.1 warning
}
int Scd40SetCommand(int command_code, uint16_t *pvalue)
{
switch (command_code)
{
case CMND_SCD40_ALTITUDE:
return scd40.setSensorAltitude(*pvalue);
break;
case CMND_SCD40_AUTOMODE:
return scd40.setAutomaticSelfCalibrationEnabled((bool) (*pvalue));
break;
case CMND_SCD40_TEMPOFFSET:
return scd40.setTemperatureOffset(*pvalue);
break;
case CMND_SCD40_PRESSURE:
return scd40.setAmbientPressure(*pvalue);
break;
case CMND_SCD40_FORCEDRECALIBRATION:
return scd40.performForcedRecalibration(*pvalue);
break;
default:
// else for Unknown command
break;
}
return 0; // Fix GCC 10.1 warning
}
/*********************************************************************************************\
* Command Sensor42
\*********************************************************************************************/
bool Scd40CommandSensor()
{
char command[CMDSZ];
bool serviced = true;
uint8_t prefix_len = strlen(D_CMND_SCD40);
int error;
if (!strncasecmp_P(XdrvMailbox.topic, PSTR(D_CMND_SCD40), prefix_len)) { // prefix
int command_code = GetCommandCode(command, sizeof(command), XdrvMailbox.topic + prefix_len, kSCD40_Commands);
// not supported here: readMeasurement, getDataReadyStatus, getSerialNumber, measure_single_shot, measure_single_shot_rht_only
switch (command_code) {
case CMND_SCD40_ALTITUDE:
case CMND_SCD40_AUTOMODE:
case CMND_SCD40_TEMPOFFSET:
case CMND_SCD40_PRESSURE: // write-only
case CMND_SCD40_FORCEDRECALIBRATION: // write-only
case CMND_SCD40_SELFTEST: // read-only
{
uint16_t value = 0;
if (XdrvMailbox.data_len > 0)
{
if (command_code != CMND_SCD40_SELFTEST) {
value = XdrvMailbox.payload;
error = Scd40SetCommand(command_code, &value);
Response_P(S_JSON_SCD40_COMMAND_NVALUE, command, error?-1:0);
} else {
serviced = false;
break;
}
}
else
{
if ((command_code != CMND_SCD40_PRESSURE) && (command_code != CMND_SCD40_FORCEDRECALIBRATION)) {
error = Scd40GetCommand(command_code, &value);
Response_P(S_JSON_SCD40_COMMAND_NVALUE, command, error?-1:value);
} else {
serviced = false;
break;
}
}
}
break;
case CMND_SCD40_START_MEASUREMENT_LOW_POWER:
{
error = scd40.startLowPowerPeriodicMeasurement();
Response_P(S_JSON_SCD40_COMMAND_NVALUE, command, error?-1:0);
}
break;
case CMND_SCD40_START_MEASUREMENT:
{
error = scd40.startPeriodicMeasurement();
Response_P(S_JSON_SCD40_COMMAND_NVALUE, command, error?-1:0);
}
break;
case CMND_SCD40_STOP_MEASUREMENT:
{
error = scd40.stopPeriodicMeasurement();
Response_P(S_JSON_SCD40_COMMAND_NVALUE, command, error?-1:0);
}
break;
case CMND_SCD40_PERSIST:
{
error = scd40.persistSettings();
Response_P(S_JSON_SCD40_COMMAND_NVALUE, command, error?-1:0);
}
break;
case CMND_SCD40_REINIT:
{
error = scd40.reinit();
Response_P(S_JSON_SCD40_COMMAND_NVALUE, command, error?-1:0);
}
break;
case CMND_SCD40_FACTORYRESET:
{
error = scd40.performFactoryReset();
Response_P(S_JSON_SCD40_COMMAND_NVALUE, command, error?-1:0);
}
break;
case CMND_SCD40_SINGLESHOT:
{
error = scd40.measureSingleShot();
Response_P(S_JSON_SCD40_COMMAND_NVALUE, command, error?-1:0);
}
break;
case CMND_SCD40_SINGLESHOT_RHT_ONLY:
{
error = scd40.measureSingleShotRhtOnly();
Response_P(S_JSON_SCD40_COMMAND_NVALUE, command, error?-1:0);
}
break;
default:
// else for Unknown command
serviced = false;
break;
}
} else {
serviced = false;
}
return serviced;
}
void Scd40Show(bool json)
{
if (scd40IsDataValid)
{
float t = ConvertTemp(scd40_Temp);
float h = ConvertHumidity(scd40_Humid);
if (json) {
ResponseAppend_P(PSTR(",\"SCD40\":{\"" D_JSON_CO2 "\":%d,\"" D_JSON_ECO2 "\":%d,"), scd40_CO2, scd40_CO2EAvg);
ResponseAppendTHD(t, h);
ResponseJsonEnd();
#ifdef USE_DOMOTICZ
if (0 == TasmotaGlobal.tele_period) {
DomoticzSensor(DZ_AIRQUALITY, scd40_CO2);
DomoticzTempHumPressureSensor(t, h);
}
#endif // USE_DOMOTICZ
#ifdef USE_WEBSERVER
} else {
WSContentSend_PD(HTTP_SNS_CO2EAVG, "SCD40", scd40_CO2EAvg);
WSContentSend_PD(HTTP_SNS_CO2, "SCD40", scd40_CO2);
WSContentSend_THD("SCD40", t, h);
#endif // USE_WEBSERVER
}
}
}
/*********************************************************************************************\
* Interface
\*********************************************************************************************/
bool Xsns92(uint32_t function)
{
if (!I2cEnabled(XI2C_62)) { return false; }
bool result = false;
if (FUNC_INIT == function) {
Scd40Detect();
}
else if (scd40Found) {
switch (function) {
case FUNC_EVERY_SECOND:
Scd40Update();
break;
case FUNC_COMMAND:
result = Scd40CommandSensor();
break;
case FUNC_JSON_APPEND:
Scd40Show(1);
break;
#ifdef USE_WEBSERVER
case FUNC_WEB_SENSOR:
Scd40Show(0);
break;
#endif // USE_WEBSERVER
}
}
return result;
}
#endif // USE_SCD40
#endif // USE_I2C