Tasmota/tasmota/xsns_06_dht.ino

285 lines
8.3 KiB
C++

/*
xsns_06_dht.ino - DHTxx, AM23xx and SI7021 temperature and humidity sensor support for Tasmota
Copyright (C) 2020 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)
*
* This version is based on ESPEasy _P005_DHT.ino 20191201
\*********************************************************************************************/
#define XSNS_06 6
#define DHT_MAX_SENSORS 4
#define DHT_MAX_RETRY 8
uint8_t dht_data[5];
uint8_t dht_sensors = 0;
uint8_t dht_pin_out = 0; // Shelly GPIO00 output only
bool dht_active = true; // DHT configured
bool dht_dual_mode = false; // Single pin mode
struct DHTSTRUCT {
uint8_t pin;
uint8_t type;
uint8_t lastresult;
char stype[12];
float t = NAN;
float h = NAN;
} Dht[DHT_MAX_SENSORS];
bool DhtWaitState(uint32_t sensor, uint32_t level)
{
unsigned long timeout = micros() + 100;
while (digitalRead(Dht[sensor].pin) != level) {
if (TimeReachedUsec(timeout)) {
PrepLog_P2(LOG_LEVEL_DEBUG, PSTR(D_LOG_DHT D_TIMEOUT_WAITING_FOR " %s " D_PULSE),
(level) ? D_START_SIGNAL_HIGH : D_START_SIGNAL_LOW);
return false;
}
delayMicroseconds(1);
}
return true;
}
bool DhtRead(uint32_t sensor)
{
dht_data[0] = dht_data[1] = dht_data[2] = dht_data[3] = dht_data[4] = 0;
if (!dht_dual_mode) {
pinMode(Dht[sensor].pin, OUTPUT);
digitalWrite(Dht[sensor].pin, LOW);
} else {
digitalWrite(dht_pin_out, LOW);
}
switch (Dht[sensor].type) {
case GPIO_DHT11: // DHT11
delay(19); // minimum 18ms
break;
case GPIO_DHT22: // DHT21, DHT22, AM2301, AM2302, AM2321
// delay(2); // minimum 1ms
delayMicroseconds(2000); // See https://github.com/arendst/Tasmota/pull/7468#issuecomment-647067015
break;
case GPIO_SI7021: // iTead SI7021
delayMicroseconds(500);
break;
}
if (!dht_dual_mode) {
pinMode(Dht[sensor].pin, INPUT_PULLUP);
} else {
digitalWrite(dht_pin_out, HIGH);
}
switch (Dht[sensor].type) {
case GPIO_DHT11: // DHT11
case GPIO_DHT22: // DHT21, DHT22, AM2301, AM2302, AM2321
delayMicroseconds(50);
break;
case GPIO_SI7021: // iTead SI7021
delayMicroseconds(20); // See: https://github.com/letscontrolit/ESPEasy/issues/1798
break;
}
/*
bool error = false;
noInterrupts();
if (DhtWaitState(sensor, 0) && DhtWaitState(sensor, 1) && DhtWaitState(sensor, 0)) {
for (uint32_t i = 0; i < 5; i++) {
int data = 0;
for (uint32_t j = 0; j < 8; j++) {
if (!DhtWaitState(sensor, 1)) {
error = true;
break;
}
delayMicroseconds(35); // Was 30
if (digitalRead(Dht[sensor].pin)) {
data |= (1 << (7 - j));
}
if (!DhtWaitState(sensor, 0)) {
error = true;
break;
}
}
if (error) { break; }
dht_data[i] = data;
}
} else {
error = true;
}
interrupts();
if (error) { return false; }
*/
uint32_t i = 0;
noInterrupts();
if (DhtWaitState(sensor, 0) && DhtWaitState(sensor, 1) && DhtWaitState(sensor, 0)) {
for (i = 0; i < 40; i++) {
if (!DhtWaitState(sensor, 1)) { break; }
delayMicroseconds(35); // Was 30
if (digitalRead(Dht[sensor].pin)) {
dht_data[i / 8] |= (1 << (7 - i % 8));
}
if (!DhtWaitState(sensor, 0)) { break; }
}
}
interrupts();
if (i < 40) { return false; }
uint8_t checksum = (dht_data[0] + dht_data[1] + dht_data[2] + dht_data[3]) & 0xFF;
if (dht_data[4] != checksum) {
char hex_char[15];
AddLog_P2(LOG_LEVEL_DEBUG, PSTR(D_LOG_DHT D_CHECKSUM_FAILURE " %s =? %02X"),
ToHex_P(dht_data, 5, hex_char, sizeof(hex_char), ' '), checksum);
return false;
}
float temperature = NAN;
float humidity = NAN;
switch (Dht[sensor].type) {
case GPIO_DHT11:
humidity = dht_data[0];
temperature = dht_data[2] + ((float)dht_data[3] * 0.1f); // Issue #3164
break;
case GPIO_DHT22:
case GPIO_SI7021:
humidity = ((dht_data[0] << 8) | dht_data[1]) * 0.1;
temperature = (((dht_data[2] & 0x7F) << 8 ) | dht_data[3]) * 0.1;
if (dht_data[2] & 0x80) {
temperature *= -1;
}
break;
}
if (isnan(temperature) || isnan(humidity)) {
AddLog_P(LOG_LEVEL_DEBUG, PSTR(D_LOG_DHT "Invalid NAN reading"));
return false;
}
if (humidity > 100) { humidity = 100.0; }
if (humidity < 0) { humidity = 0.1; }
Dht[sensor].h = ConvertHumidity(humidity);
Dht[sensor].t = ConvertTemp(temperature);
Dht[sensor].lastresult = 0;
return true;
}
/********************************************************************************************/
bool DhtPinState()
{
if ((XdrvMailbox.index >= GPIO_DHT11) && (XdrvMailbox.index <= GPIO_SI7021)) {
if (dht_sensors < DHT_MAX_SENSORS) {
Dht[dht_sensors].pin = XdrvMailbox.payload;
Dht[dht_sensors].type = XdrvMailbox.index;
dht_sensors++;
XdrvMailbox.index = GPIO_DHT11;
} else {
XdrvMailbox.index = 0;
}
return true;
}
return false;
}
void DhtInit(void)
{
if (dht_sensors) {
if (PinUsed(GPIO_DHT11_OUT)) {
dht_pin_out = Pin(GPIO_DHT11_OUT);
dht_dual_mode = true; // Dual pins mode as used by Shelly
dht_sensors = 1; // We only support one sensor in pseudo mode
pinMode(dht_pin_out, OUTPUT);
}
for (uint32_t i = 0; i < dht_sensors; i++) {
pinMode(Dht[i].pin, INPUT_PULLUP);
Dht[i].lastresult = DHT_MAX_RETRY; // Start with NAN
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%c%02d"), Dht[i].stype, IndexSeparator(), Dht[i].pin);
}
}
AddLog_P2(LOG_LEVEL_DEBUG, PSTR(D_LOG_DHT "(v5) " D_SENSORS_FOUND " %d"), dht_sensors);
} else {
dht_active = false;
}
}
void DhtEverySecond(void)
{
if (uptime &1) { // Every 2 seconds
for (uint32_t sensor = 0; sensor < dht_sensors; sensor++) {
// DHT11 and AM2301 25mS per sensor, SI7021 5mS per sensor
if (!DhtRead(sensor)) {
Dht[sensor].lastresult++;
if (Dht[sensor].lastresult > DHT_MAX_RETRY) { // Reset after 8 misses
Dht[sensor].t = NAN;
Dht[sensor].h = NAN;
}
}
}
}
}
void DhtShow(bool json)
{
for (uint32_t i = 0; i < dht_sensors; i++) {
TempHumDewShow(json, ((0 == tele_period) && (0 == i)), Dht[i].stype, Dht[i].t, Dht[i].h);
}
}
/*********************************************************************************************\
* Interface
\*********************************************************************************************/
bool Xsns06(uint8_t function)
{
bool result = false;
if (dht_active) {
switch (function) {
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
case FUNC_INIT:
DhtInit();
break;
case FUNC_PIN_STATE:
result = DhtPinState();
break;
}
}
return result;
}
#endif // USE_DHT