Tasmota/sonoff/xsns_02_analog.ino

193 lines
5.7 KiB
C++

/*
xsns_02_analog.ino - ESP8266 ADC support for Sonoff-Tasmota
Copyright (C) 2019 Theo Arends
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 <http://www.gnu.org/licenses/>.
*/
#ifndef USE_ADC_VCC
/*********************************************************************************************\
* ADC support
\*********************************************************************************************/
#define XSNS_02 2
#define TO_CELSIUS(x) ((x) - 273.15)
#define TO_KELVIN(x) ((x) + 273.15)
// Parameters for equation
#define ANALOG_V33 3.3 // ESP8266 Analog voltage
#define ANALOG_T0 TO_KELVIN(25.0) // 25 degrees Celcius in Kelvin (= 298.15)
// Shelly 2.5 NTC Thermistor
// 3V3 --- ANALOG_NTC_BRIDGE_RESISTANCE ---v--- NTC --- Gnd
// |
// ADC0
#define ANALOG_NTC_BRIDGE_RESISTANCE 32000.0 // NTC Voltage bridge resistor
#define ANALOG_NTC_RESISTANCE 10000.0 // NTC Resistance
#define ANALOG_NTC_B_COEFFICIENT 3350.0 // NTC Beta Coefficient
// LDR parameters
// 3V3 --- LDR ---v--- ANALOG_LDR_BRIDGE_RESISTANCE --- Gnd
// |
// ADC0
#define ANALOG_LDR_BRIDGE_RESISTANCE 10000.0 // LDR Voltage bridge resistor
#define ANALOG_LDR_LUX_CALC_SCALAR 12518931 // Experimental
#define ANALOG_LDR_LUX_CALC_EXPONENT -1.405 // Experimental
uint16_t adc_last_value = 0;
float adc_temp = 0;
uint16_t AdcRead(uint8_t factor)
{
// factor 1 = 2 samples
// factor 2 = 4 samples
// factor 3 = 8 samples
// factor 4 = 16 samples
// factor 5 = 32 samples
uint8_t samples = 1 << factor;
uint16_t analog = 0;
for (uint8_t i = 0; i < samples; i++) {
analog += analogRead(A0);
delay(1);
}
analog >>= factor;
return analog;
}
#ifdef USE_RULES
void AdcEvery250ms(void)
{
if (ADC0_INPUT == my_adc0) {
uint16_t new_value = AdcRead(5);
if ((new_value < adc_last_value -10) || (new_value > adc_last_value +10)) {
adc_last_value = new_value;
uint16_t value = adc_last_value / 10;
Response_P(PSTR("{\"ANALOG\":{\"A0div10\":%d}}"), (value > 99) ? 100 : value);
XdrvRulesProcess();
}
}
}
#endif // USE_RULES
uint16_t AdcGetLux()
{
int adc = AdcRead(2);
// Source: https://www.allaboutcircuits.com/projects/design-a-luxmeter-using-a-light-dependent-resistor/
double resistorVoltage = ((double)adc / 1023) * ANALOG_V33;
double ldrVoltage = ANALOG_V33 - resistorVoltage;
double ldrResistance = ldrVoltage / resistorVoltage * ANALOG_LDR_BRIDGE_RESISTANCE;
double ldrLux = ANALOG_LDR_LUX_CALC_SCALAR * FastPrecisePow(ldrResistance, ANALOG_LDR_LUX_CALC_EXPONENT);
return (uint16_t)ldrLux;
}
void AdcEverySecond(void)
{
if (ADC0_TEMP == my_adc0) {
int adc = AdcRead(2);
// Steinhart-Hart equation for thermistor as temperature sensor
double Rt = (adc * ANALOG_NTC_BRIDGE_RESISTANCE) / (1024.0 * ANALOG_V33 - (double)adc);
double T = ANALOG_NTC_B_COEFFICIENT / (ANALOG_NTC_B_COEFFICIENT / ANALOG_T0 + log(Rt / ANALOG_NTC_RESISTANCE));
adc_temp = ConvertTemp(TO_CELSIUS(T));
}
}
void AdcShow(bool json)
{
if (ADC0_INPUT == my_adc0) {
uint16_t analog = AdcRead(5);
if (json) {
ResponseAppend_P(PSTR(",\"ANALOG\":{\"A0\":%d}"), analog);
#ifdef USE_WEBSERVER
} else {
WSContentSend_PD(HTTP_SNS_ANALOG, "", 0, analog);
#endif // USE_WEBSERVER
}
}
else if (ADC0_TEMP == my_adc0) {
char temperature[33];
dtostrfd(adc_temp, Settings.flag2.temperature_resolution, temperature);
if (json) {
ResponseAppend_P(JSON_SNS_TEMP, "ANALOG", temperature);
#ifdef USE_DOMOTICZ
if (0 == tele_period) {
DomoticzSensor(DZ_TEMP, temperature);
}
#endif // USE_DOMOTICZ
#ifdef USE_KNX
if (0 == tele_period) {
KnxSensor(KNX_TEMPERATURE, adc_temp);
}
#endif // USE_KNX
#ifdef USE_WEBSERVER
} else {
WSContentSend_PD(HTTP_SNS_TEMP, "", temperature, TempUnit());
#endif // USE_WEBSERVER
}
}
else if (ADC0_LIGHT == my_adc0) {
uint16_t adc_light = AdcGetLux();
if (json) {
ResponseAppend_P(JSON_SNS_ILLUMINANCE, "ANALOG", adc_light);
#ifdef USE_DOMOTICZ
if (0 == tele_period) {
DomoticzSensor(DZ_ILLUMINANCE, adc_light);
}
#endif // USE_DOMOTICZ
#ifdef USE_WEBSERVER
} else {
WSContentSend_PD(HTTP_SNS_ILLUMINANCE, "", adc_light);
#endif // USE_WEBSERVER
}
}
}
/*********************************************************************************************\
* Interface
\*********************************************************************************************/
bool Xsns02(uint8_t function)
{
bool result = false;
if ((ADC0_INPUT == my_adc0) || (ADC0_TEMP == my_adc0) || (ADC0_LIGHT == my_adc0)) {
switch (function) {
#ifdef USE_RULES
case FUNC_EVERY_250_MSECOND:
AdcEvery250ms();
break;
#endif // USE_RULES
case FUNC_EVERY_SECOND:
AdcEverySecond();
break;
case FUNC_JSON_APPEND:
AdcShow(1);
break;
#ifdef USE_WEBSERVER
case FUNC_WEB_SENSOR:
AdcShow(0);
break;
#endif // USE_WEBSERVER
}
}
return result;
}
#endif // USE_ADC_VCC