Tasmota/sonoff/xsns_06_dht.ino

268 lines
7.2 KiB
C++

/*
xsns_06_dht.ino - DHTxx, AM23xx and SI7021 temperature and humidity sensor 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/>.
*/
#ifdef USE_DHT
/*********************************************************************************************\
* DHT11, AM2301 (DHT21, DHT22, AM2302, AM2321), SI7021 - Temperature and Humidy
*
* Reading temperature or humidity takes about 250 milliseconds!
* Sensor readings may also be up to 2 seconds 'old' (its a very slow sensor)
* Source: Adafruit Industries https://github.com/adafruit/DHT-sensor-library
\*********************************************************************************************/
#define XSNS_06 6
#define DHT_MAX_SENSORS 3
#define DHT_MAX_RETRY 8
uint32_t dht_max_cycles;
uint8_t dht_data[5];
uint8_t dht_sensors = 0;
struct DHTSTRUCT {
uint8_t pin;
uint8_t type;
char stype[12];
uint32_t lastreadtime;
uint8_t lastresult;
float t = NAN;
float h = NAN;
} Dht[DHT_MAX_SENSORS];
void DhtReadPrep(void)
{
for (uint8_t i = 0; i < dht_sensors; i++) {
digitalWrite(Dht[i].pin, HIGH);
}
}
int32_t DhtExpectPulse(uint8_t sensor, bool level)
{
int32_t count = 0;
while (digitalRead(Dht[sensor].pin) == level) {
if (count++ >= (int32_t)dht_max_cycles) {
return -1; // Timeout
}
}
return count;
}
bool DhtRead(uint8_t sensor)
{
int32_t cycles[80];
uint8_t error = 0;
dht_data[0] = dht_data[1] = dht_data[2] = dht_data[3] = dht_data[4] = 0;
// digitalWrite(Dht[sensor].pin, HIGH);
// delay(250);
if (Dht[sensor].lastresult > DHT_MAX_RETRY) {
Dht[sensor].lastresult = 0;
digitalWrite(Dht[sensor].pin, HIGH); // Retry read prep
delay(250);
}
pinMode(Dht[sensor].pin, OUTPUT);
digitalWrite(Dht[sensor].pin, LOW);
if (GPIO_SI7021 == Dht[sensor].type) {
delayMicroseconds(500);
} else {
delay(20);
}
noInterrupts();
digitalWrite(Dht[sensor].pin, HIGH);
delayMicroseconds(40);
pinMode(Dht[sensor].pin, INPUT_PULLUP);
delayMicroseconds(10);
if (-1 == DhtExpectPulse(sensor, LOW)) {
AddLog_P(LOG_LEVEL_DEBUG, PSTR(D_LOG_DHT D_TIMEOUT_WAITING_FOR " " D_START_SIGNAL_LOW " " D_PULSE));
error = 1;
}
else if (-1 == DhtExpectPulse(sensor, HIGH)) {
AddLog_P(LOG_LEVEL_DEBUG, PSTR(D_LOG_DHT D_TIMEOUT_WAITING_FOR " " D_START_SIGNAL_HIGH " " D_PULSE));
error = 1;
}
else {
for (int i = 0; i < 80; i += 2) {
cycles[i] = DhtExpectPulse(sensor, LOW);
cycles[i+1] = DhtExpectPulse(sensor, HIGH);
}
}
interrupts();
if (error) { return false; }
for (int i = 0; i < 40; ++i) {
int32_t lowCycles = cycles[2*i];
int32_t highCycles = cycles[2*i+1];
if ((-1 == lowCycles) || (-1 == highCycles)) {
AddLog_P(LOG_LEVEL_DEBUG, PSTR(D_LOG_DHT D_TIMEOUT_WAITING_FOR " " D_PULSE));
return false;
}
dht_data[i/8] <<= 1;
if (highCycles > lowCycles) {
dht_data[i / 8] |= 1;
}
}
uint8_t checksum = (dht_data[0] + dht_data[1] + dht_data[2] + dht_data[3]) & 0xFF;
if (dht_data[4] != checksum) {
AddLog_P2(LOG_LEVEL_DEBUG, PSTR(D_LOG_DHT D_CHECKSUM_FAILURE " %02X, %02X, %02X, %02X, %02X =? %02X"),
dht_data[0], dht_data[1], dht_data[2], dht_data[3], dht_data[4], checksum);
return false;
}
return true;
}
void DhtReadTempHum(uint8_t sensor)
{
if ((NAN == Dht[sensor].h) || (Dht[sensor].lastresult > DHT_MAX_RETRY)) { // Reset after 8 misses
Dht[sensor].t = NAN;
Dht[sensor].h = NAN;
}
if (DhtRead(sensor)) {
switch (Dht[sensor].type) {
case GPIO_DHT11:
Dht[sensor].h = dht_data[0];
Dht[sensor].t = dht_data[2] + ((float)dht_data[3] * 0.1f); // Issue #3164
break;
case GPIO_DHT22:
case GPIO_SI7021:
Dht[sensor].h = ((dht_data[0] << 8) | dht_data[1]) * 0.1;
Dht[sensor].t = (((dht_data[2] & 0x7F) << 8 ) | dht_data[3]) * 0.1;
if (dht_data[2] & 0x80) {
Dht[sensor].t *= -1;
}
break;
}
Dht[sensor].t = ConvertTemp(Dht[sensor].t);
Dht[sensor].h = ConvertHumidity(Dht[sensor].h);
Dht[sensor].lastresult = 0;
} else {
Dht[sensor].lastresult++;
}
}
bool DhtSetup(uint8_t pin, uint8_t type)
{
bool success = false;
if (dht_sensors < DHT_MAX_SENSORS) {
Dht[dht_sensors].pin = pin;
Dht[dht_sensors].type = type;
dht_sensors++;
success = true;
}
return success;
}
/********************************************************************************************/
void DhtInit(void)
{
dht_max_cycles = microsecondsToClockCycles(1000); // 1 millisecond timeout for reading pulses from DHT sensor.
for (uint8_t i = 0; i < dht_sensors; i++) {
pinMode(Dht[i].pin, INPUT_PULLUP);
Dht[i].lastreadtime = 0;
Dht[i].lastresult = 0;
GetTextIndexed(Dht[i].stype, sizeof(Dht[i].stype), Dht[i].type, kSensorNames);
if (dht_sensors > 1) {
snprintf_P(Dht[i].stype, sizeof(Dht[i].stype), PSTR("%s-%02d"), Dht[i].stype, Dht[i].pin);
}
}
}
void DhtEverySecond(void)
{
if (uptime &1) {
// <1mS
DhtReadPrep();
} else {
for (uint8_t i = 0; i < dht_sensors; i++) {
// DHT11 and AM2301 25mS per sensor, SI7021 5mS per sensor
DhtReadTempHum(i);
}
}
}
void DhtShow(bool json)
{
for (uint8_t i = 0; i < dht_sensors; i++) {
char temperature[33];
dtostrfd(Dht[i].t, Settings.flag2.temperature_resolution, temperature);
char humidity[33];
dtostrfd(Dht[i].h, Settings.flag2.humidity_resolution, humidity);
if (json) {
ResponseAppend_P(JSON_SNS_TEMPHUM, Dht[i].stype, temperature, humidity);
#ifdef USE_DOMOTICZ
if ((0 == tele_period) && (0 == i)) {
DomoticzTempHumSensor(temperature, humidity);
}
#endif // USE_DOMOTICZ
#ifdef USE_KNX
if ((0 == tele_period) && (0 == i)) {
KnxSensor(KNX_TEMPERATURE, Dht[i].t);
KnxSensor(KNX_HUMIDITY, Dht[i].h);
}
#endif // USE_KNX
#ifdef USE_WEBSERVER
} else {
WSContentSend_PD(HTTP_SNS_TEMP, Dht[i].stype, temperature, TempUnit());
WSContentSend_PD(HTTP_SNS_HUM, Dht[i].stype, humidity);
#endif // USE_WEBSERVER
}
}
}
/*********************************************************************************************\
* Interface
\*********************************************************************************************/
bool Xsns06(uint8_t function)
{
bool result = false;
if (dht_flg) {
switch (function) {
case FUNC_INIT:
DhtInit();
break;
case FUNC_EVERY_SECOND:
DhtEverySecond();
break;
case FUNC_JSON_APPEND:
DhtShow(1);
break;
#ifdef USE_WEBSERVER
case FUNC_WEB_SENSOR:
DhtShow(0);
break;
#endif // USE_WEBSERVER
}
}
return result;
}
#endif // USE_DHT