Add cht8310 support (#1008)

* add CHT8310 support

* fix humidity measurement

* make chip id logic safer to prevent braking the old sensor

* fixed mistake in sensor_id

---------

Co-authored-by: Your Name <[email protected]>

src/driver/drv_cht8305.c

@@ -20,12 +20,23 @@ static byte channel_temp = 0, channel_humid = 0;
 static float g_temp = 0.0, g_humid = 0.0;
 static softI2C_t g_softI2C;
 static float g_calTemp = 0, g_calHum = 0;
+static uint16_t sensor_id=0;
 
 
 static void CHT8305_ReadEnv(float* temp, float* hum) {
 	uint8_t buff[4];
 	unsigned int th, tl, hh, hl;
 
+	if(sensor_id==0x8215)
+	{
+		//Make dymmy write to Oneshot register to trigger a measurement, sensor is otherwise sleeping
+		Soft_I2C_Start(&g_softI2C, CHT8305_I2C_ADDR);
+		Soft_I2C_WriteByte(&g_softI2C, 0x0F);			
+		Soft_I2C_WriteByte(&g_softI2C, 0x00);			
+		Soft_I2C_WriteByte(&g_softI2C, 0x00);
+		Soft_I2C_Stop(&g_softI2C);
+	}
+
 	Soft_I2C_Start(&g_softI2C, CHT8305_I2C_ADDR);
 	Soft_I2C_WriteByte(&g_softI2C, 0x00);
 	Soft_I2C_Stop(&g_softI2C);
@@ -36,14 +47,33 @@ static void CHT8305_ReadEnv(float* temp, float* hum) {
 	Soft_I2C_ReadBytes(&g_softI2C, buff, 4);
 	Soft_I2C_Stop(&g_softI2C);
 
+	//In case we have the new sensor 8310, overwrite humidity data reading it from 0x01, as it cannot be directrly read from 0x00, there is parity
+	if(sensor_id==0x8215)
+	{
+		Soft_I2C_Start(&g_softI2C, CHT8305_I2C_ADDR);
+		Soft_I2C_WriteByte(&g_softI2C, 0x01);
+		Soft_I2C_Stop(&g_softI2C);
+
+		Soft_I2C_Start(&g_softI2C, CHT8305_I2C_ADDR | 1);
+		Soft_I2C_ReadBytes(&g_softI2C, buff+2, 2);
+		Soft_I2C_Stop(&g_softI2C);
+	}
+
 	th = buff[0];
 	tl = buff[1];
 	hh = buff[2];
 	hl = buff[3];
 
-	(*temp) = ((th << 8 | tl) * 165.0 / 65535.0 - 40.0)+ g_calTemp;
-
-	(*hum) = ((hh << 8 | hl) * 100.0 / 65535.0)+ g_calHum;
+	if(sensor_id==0x8215)
+	{
+		(*temp)=((th << 8 | tl)>>1)/128.0+g_calTemp;
+		(*hum) = ((((hh << 8 | hl) & 0x7fff) / 32768.0 ) * 100.0)+ g_calHum;
+	}
+	else
+	{
+		(*temp) = ((th << 8 | tl) * 165.0 / 65535.0 - 40.0)+ g_calTemp;
+		(*hum) = ((hh << 8 | hl) * 100.0 / 65535.0)+ g_calHum;
+	}
 
 }
 
@@ -78,10 +108,8 @@ commandResult_t CHT_cycle(const void* context, const char* cmd, const char* args
 }
 // startDriver CHT8305
 void CHT8305_Init() {
-
 	uint8_t buff[4];
 
-
 	g_softI2C.pin_clk = 9;
 	g_softI2C.pin_data = 14;
 	g_softI2C.pin_clk = PIN_FindPinIndexForRole(IOR_CHT8305_CLK, g_softI2C.pin_clk);
@@ -90,13 +118,41 @@ void CHT8305_Init() {
 	Soft_I2C_PreInit(&g_softI2C);
 
 	Soft_I2C_Start(&g_softI2C, CHT8305_I2C_ADDR);
-	Soft_I2C_WriteByte(&g_softI2C, 0xfe);			//manufacturer ID
+	Soft_I2C_WriteByte(&g_softI2C, 0xfe);			//manufacturer ID 2 bytes
 	Soft_I2C_Stop(&g_softI2C);
 	Soft_I2C_Start(&g_softI2C, CHT8305_I2C_ADDR | 1);
 	Soft_I2C_ReadBytes(&g_softI2C, buff, 2);
 	Soft_I2C_Stop(&g_softI2C);
 
-	addLogAdv(LOG_INFO, LOG_FEATURE_SENSOR, "DRV_CHT8304_init: ID: %02X %02X", buff[0], buff[1]);
+
+	//Read Sensor version separately on the last 2 bytes of the buffer
+	Soft_I2C_Start(&g_softI2C, CHT8305_I2C_ADDR);
+	Soft_I2C_WriteByte(&g_softI2C, 0xff);
+	Soft_I2C_Stop(&g_softI2C);
+
+	Soft_I2C_Start(&g_softI2C, CHT8305_I2C_ADDR | 1);
+	Soft_I2C_ReadBytes(&g_softI2C, buff+2, 2);
+	Soft_I2C_Stop(&g_softI2C);
+
+	//Identify chip ID and keep if for later use
+	sensor_id=(buff[2] << 8 | buff[3]);
+
+	addLogAdv(LOG_INFO, LOG_FEATURE_SENSOR, "DRV_CHT8305_init: ID: %02X %02X %04X", buff[0], buff[1], sensor_id);
+
+
+	if(sensor_id==0x8215)
+	{//it should be 8310 id is 0x8215, we enable low power mode, so only 50nA are drawn from sensor, 
+	//but need to write something to one shot register to trigger new measurement
+
+		Soft_I2C_Start(&g_softI2C, CHT8305_I2C_ADDR);
+		Soft_I2C_WriteByte(&g_softI2C, 0x03);			//config register
+		Soft_I2C_WriteByte(&g_softI2C, 0x48);			//enable shutdown default is 0x08 
+														//setting bit 6 enables low power mode, 
+														//to get new measurement need to write to one shot register
+		Soft_I2C_WriteByte(&g_softI2C, 0x80);			//as default 0x80
+		Soft_I2C_Stop(&g_softI2C);
+
+	}
 
 	//cmddetail:{"name":"CHT_Calibrate","args":"[DeltaTemp][DeltaHumidity]",
 	//cmddetail:"descr":"Calibrate the CHT Sensor as Tolerance is +/-2 degrees C.",