> [!NOTE] > This is an attempt at formatting what we found as documentation for the temparature sensor. > The raw text it was formatted from is kept alongside it in > [temperature-sensor-unformatted.txt](temperature-sensor-unformatted.txt). Unlike the RadiCal fan > and the relay module, no manufacturer PDF exists for this device, so this file is the only > documentation there is. ## Product parameters: Working voltage: DC4-30V (the highest should not exceed 33V) Maximum power: 0.2W Working temperature: temperature -20℃+60℃, humidity 0%RH-100%RH Control accuracy: temperature ±0.3℃(25℃), humidity ±3%RH(25℃) Output interface: RS485 communication (standard MODBUS protocol and custom common protocol), see protocol description for details Device address: 1-247 can be set, the default is 1 Baud rate: default 9600 (users can set by themselves), 8 data, 1 stop, no parity Size: 60 _ 30 _ 18 ## MODBUS protocol ### Function code used by the product: | | | | ----- | -------------------------------- | | 0x03: | Read holding register | | 0x04: | Read input register | | 0x06: | Write a single holding register | | 0x10: | write multiple holding registers | | Register type | Register address | Data content | Number of bytes | | ---------------- | ---------------- | --------------------------------------------- | --------------- | | Input register | 0x0001 | Temperature value | 2 | | | 0x0002 | Humidity value | 2 | | Holding register | 0x0101 | Device address (1~247) | 2 | | | 0x0102 | Baud rate 0:9600 1:14400 2:19200 | 2 | | | 0x0103 | Temperature correction value (/10) -10.0~10.0 | 2 | | | 0x0104 | Humidity correction value (/10) -10.0~10.0 | 2 | ### Modbus communication format: #### Host sends data frame: | | | | | | | | | | ------------- | ------------- | -------------------------- | ------------------------- | ----------------------------- | ---------------------------- | ------------- | ------------ | | Slave address | function code | Register address High byte | Register address Low byte | Number of registers High byte | Number of registers Low byte | CRC High byte | CRC Low byte | ### The slave responds to the data frame: | | | | | | | | | | | ------------- | ---------------------- | --------------- | ------------------------- | ------------------------ | ------------------------- | ------------------------ | ------------- | ------------ | | Slave address | Response function code | Number of bytes | Register 1 data High byte | Register 1 data Low byte | Register N data High byte | Register N data Low byte | CRC High byte | CRC Low byte | ### MODBUS command frame ### The host reads the temperature command frame (0x04): | Slave address | function code | Register address High byte | Register address Low byte | Number of registers High byte | Number of registers Low byte | CRC High byte | CRC Low byte | | ------------- | ------------- | -------------------------- | ------------------------- | ----------------------------- | ---------------------------- | ------------- | ------------ | | 0x01 | 0x04 | 0x00 | 0x01 | 0x00 | 0x01 | 0x60 | 0x0a | #### The slave responds to the data frame: | Slave address | function code | Number of bytes | temperature High byte | temperature Low byte | CRC High byte | CRC Low byte | | ------------- | ------------- | --------------- | --------------------- | -------------------- | ------------- | ------------ | | 0x01 | 0x04 | 0x02 | 0x01 | 0x31 | 0x79 | 0x74 | Temperature value = 0x131, converted to decimal 305, actual temperature value = 305/10 = 30.5℃ > [!NOTE] > The temperature is a signed hexadecimal number, temperature value=0xFF33, converted to decimal -205, actual temperature = -20.5℃; #### The host reads the humidity command frame (0x04): > [!WARNING] > **Both frames in this humidity section had wrong check bytes in the source we transcribed from, > and both have been corrected below.** The request was printed as `0xC1 0xCA` but `01 04 00 02 00 > 01` checksums to `0x90 0x0A`; the response was printed as `0xD1 0xBA` but `01 04 02 02 22` > checksums to `0x38 0x49`. > > Every other frame in this file is correct, as is every frame in the relay manual. They were all > checked against the CRC implementation in > [serial/src/modbus/crc.ts](../serial/src/modbus/crc.ts) by `serial/src/modbus/crc.test.ts`, which > is where the mistake surfaced. Do not "fix" these back without recomputing them. | Slave address | function code | Register address High byte | Register address Low byte | Number of registers High byte | Number of registers Low byte | CRC High byte | CRC Low byte | | ------------- | ------------- | -------------------------- | ------------------------- | ----------------------------- | ---------------------------- | ------------- | ------------ | | 0x01 | 0x04 | 0x00 | 0x02 | 0x00 | 0x01 | 0x90 | 0x0A | #### The slave responds to the data frame: | Slave address | function code | Number of bytes | humidity High byte | humidity Low byte | CRC High byte | CRC Low byte | | ------------- | ------------- | --------------- | ------------------ | ----------------- | ------------- | ------------ | | 0x01 | 0x04 | 0x02 | 0x02 | 0x22 | 0x38 | 0x49 | Humidity value=0x222, converted to decimal 546, actual humidity value=546 / 10 = 54.6%; ### Continuously read the temperature and humidity command frame (0x04): > [!NOTE] > I believe the original author meant continuously as in "multiple" and not continuously as in "over time" | Slave address | function code | Register address High byte | Register address Low byte | Number of registers High byte | Number of registers Low byte | CRC High byte | CRC Low byte | | ------------- | ------------- | -------------------------- | ------------------------- | ----------------------------- | ---------------------------- | ------------- | ------------ | | 0x01 | 0x04 | 0x00 | 0x01 | 0x00 | 0x02 | 0x20 | 0x0B | #### The slave responds to the data frame: | Slave address | function code | Number of bytes | temperature High byte | temperature Low byte | humidity High byte | humidity Low byte | CRC High byte | CRC Low byte | | ------------- | ------------- | --------------- | --------------------- | -------------------- | ------------------ | ----------------- | ------------- | ------------ | | 0x01 | 0x04 | 0x04 | 0x01 | 0x31 | 0x02 | 0x22 | 0x2A | 0xCE | ### Read the content of the holding register (0x03): #### Take reading the slave address as an example: | Slave address | function code | Register address High byte | Register address Low byte | Number of registers High byte | Number of registers Low byte | CRC High byte | CRC Low byte | | ------------- | ------------- | -------------------------- | ------------------------- | ----------------------------- | ---------------------------- | ------------- | ------------ | | 0x01 | 0x03 | 0x01 | 0x01 | 0x00 | 0x01 | 0xD4 | 0x0F | #### Slave response frame: | Slave address | function code | Number of bytes | Slave address High byte | Slave address Low byte | CRC High byte | CRC Low byte | | ------------- | ------------- | --------------- | ----------------------- | ---------------------- | ------------- | ------------ | | 0x01 | 0x03 | 0x02 | 0x00 | 0x01 | 0x30 | 0x18 | ### Modify the content of the holding register (0x06): #### Take the modification of the slave address as an example: | Slave address | function code | Register address High byte | Register address Low byte | Register value High byte | Register value Low byte | CRC High byte | CRC Low byte | | ------------- | ------------- | -------------------------- | ------------------------- | ------------------------ | ----------------------- | ------------- | ------------ | | 0x01 | 0x06 | 0x01 | 0x01 | 0x00 | 0x08 | 0xD4 | 0x0F | Modify slave address: 0x08 = 8 #### Slave response frame (same as sending): | Slave address | function code | Register address High byte | Register address Low byte | Register value High byte | Register value Low byte | CRC High byte | CRC Low byte | | ------------- | ------------- | -------------------------- | ------------------------- | ------------------------ | ----------------------- | ------------- | ------------ | | 0x01 | 0x06 | 0x01 | 0x01 | 0x00 | 0x08 | 0xD4 | 0x0F | ### Continuously modify the holding register (0x10): | Slave address | function code | initial address High byte | initial address Low byte | Number of registers High byte | Number of registers Low byte | Number of bytes | Register 1 high byte | Register 1 low byte | Register 2 high byte | Register 2 low byte | CRC High byte | CRC Low byte | | ------------- | ------------- | ------------------------- | ------------------------ | ----------------------------- | ---------------------------- | --------------- | -------------------- | ------------------- | -------------------- | ------------------- | ------------- | ------------ | | 0x01 | 0x06 | 0x01 | 0x01 | 0x00 | 0x02 | 0x04 | 0x00 | 0x20 | 0x25 | 0x80 | 0x25 | 0x09 | Modify slave address: 0x20 = 32 Baud rate: 0x2580 = 9600 #### Slave response frame: | Slave address | function code | Register address High byte | Register address Low byte | Number of registers High byte | Number of registers Low byte | CRC High byte | CRC Low byte | | ------------- | ------------- | -------------------------- | ------------------------- | ----------------------------- | ---------------------------- | ------------- | ------------ | | 0x01 | 0x06 | 0x00 | 0x11 | 0x00 | 0x04 | 0xD4 | 0x0F | ## Normal version agreement The default baud rate is 9600 (users can set by themselves), 8 bits of data, 1 bit of stop, no parity RS485 communication | Serial command | Description | | -------------- | ------------------------------------------------------------------------------------------------ | | READ | Trigger a temperature and humidity report (27.4℃, 67.7% temperature 27.4℃ humidity 67.7%) | | AUTO | Start the automatic temperature and humidity report function (Same as above) | | STOP | Stop the automatic reporting of temperature and humidity | | BR:XXXX | Set the baud rate 9600~19200 (BR: 9600 baud rate is 9600) | | TC:XX.X | Set temperature calibration (-10.0~10.0) (TC:02.0 temperature correction value is 2.0℃) | | HC:XX.X | Set humidity calibration (-10.0~10.0) (HC:-05.1 Humidity correction value is -5.1%) | | HZ:XXX | Set the temperature and humidity report rate (0.5,1,2,5,10) (HZ: 2 automatic reporting rate 2Hz) | | PARAM | Read current system settings， | PARAM instruction: TC:0.0,HC:0.0,BR:9600,HZ:1 -> Temperature correction value 0.0 Humidity correction value 0.0 Baud rate 9600 Report rate 1Hz SLAVE_ADD:1 ->MODBUS slave address 0x01