Tasmota/sonoff/xsns_26_lm75ad.ino

128 lines
3.6 KiB
C++

/*
xsns_26_lm75ad.ino - Support for I2C LM75AD Temperature Sensor
Copyright (C) 2019 Andre Thomas and 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_I2C
#ifdef USE_LM75AD
/*********************************************************************************************\
* LM75AD - Temperature
*
* Docs at https://www.nxp.com/docs/en/data-sheet/LM75A.pdf
*
* I2C Address: 0x48 - 0x4F
\*********************************************************************************************/
#define XSNS_26 26
#define LM75AD_ADDRESS1 0x48
#define LM75AD_ADDRESS2 0x49
#define LM75AD_ADDRESS3 0x4A
#define LM75AD_ADDRESS4 0x4B
#define LM75AD_ADDRESS5 0x4C
#define LM75AD_ADDRESS6 0x4D
#define LM75AD_ADDRESS7 0x4E
#define LM75AD_ADDRESS8 0x4F
#define LM75_TEMP_REGISTER 0x00
#define LM75_CONF_REGISTER 0x01
#define LM75_THYST_REGISTER 0x02
#define LM75_TOS_REGISTER 0x03
uint8_t lm75ad_type = 0;
uint8_t lm75ad_address;
uint8_t lm75ad_addresses[] = { LM75AD_ADDRESS1, LM75AD_ADDRESS2, LM75AD_ADDRESS3, LM75AD_ADDRESS4, LM75AD_ADDRESS5, LM75AD_ADDRESS6, LM75AD_ADDRESS7, LM75AD_ADDRESS8 };
void LM75ADDetect(void)
{
if (lm75ad_type) { return; }
uint16_t buffer;
for (uint32_t i = 0; i < sizeof(lm75ad_addresses); i++) {
lm75ad_address = lm75ad_addresses[i];
if (I2cValidRead16(&buffer, lm75ad_address, LM75_THYST_REGISTER)) {
if (buffer == 0x4B00) {
lm75ad_type = 1;
AddLog_P2(LOG_LEVEL_DEBUG, S_LOG_I2C_FOUND_AT, "LM75AD", lm75ad_address);
break;
}
}
}
}
float LM75ADGetTemp(void) {
int16_t sign = 1;
uint16_t t = I2cRead16(lm75ad_address, LM75_TEMP_REGISTER);
if (t & 0x8000) { // we are getting a negative temperature value
t = (~t) +0x20;
sign = -1;
}
t = t >> 5; // shift value into place (5 LSB not used)
return ConvertTemp(sign * t * 0.125);
}
void LM75ADShow(bool json)
{
if (lm75ad_type) {
float t = LM75ADGetTemp();
char temperature[33];
dtostrfd(t, Settings.flag2.temperature_resolution, temperature);
if (json) {
ResponseAppend_P(PSTR(",\"LM75AD\":{\"" D_JSON_TEMPERATURE "\":%s}"), temperature);
#ifdef USE_DOMOTICZ
if (0 == tele_period) DomoticzSensor(DZ_TEMP, temperature);
#endif // USE_DOMOTICZ
#ifdef USE_WEBSERVER
} else {
WSContentSend_PD(HTTP_SNS_TEMP, "LM75AD", temperature, TempUnit());
#endif // USE_WEBSERVER
}
}
}
/*********************************************************************************************\
* Interface
\*********************************************************************************************/
bool Xsns26(uint8_t function)
{
bool result = false;
if (i2c_flg) {
switch (function) {
case FUNC_EVERY_SECOND:
LM75ADDetect();
break;
case FUNC_JSON_APPEND:
LM75ADShow(1);
break;
#ifdef USE_WEBSERVER
case FUNC_WEB_SENSOR:
LM75ADShow(0);
break;
#endif // USE_WEBSERVER
}
}
return result;
}
#endif // USE_LM75AD
#endif // USE_I2C