Data Sheet

PS: The command will return the temperature reading. The return temperature reading is using Celsius
scale. If the temperature is above 0 Celsius, the first four bits of High will be all 0. If the temperature is
below 0 Celsius, the first four bits of High will be all 1. The last 4 bits of High together with the Low
bits stands for 12bits temperature. The resolution is 0.1. When the reading is invalid, it returns 0xFF
0xFF
Example:
Command:
0x55 0xaa 0x11 0x00 0x03 0x13(SUM)
Return:
0x55 0xaa 0x11 0x02 0x03 0xF0 0x0A 0x11 (+1 Celsius Degree)
0x55 0xaa 0x11 0x02 0x03 0x00 0x0A 0x20 (-1 Celsius Degree)
0x55 0xaa 0x11 0x02 0x03 0xFF 0xFF 0x20 (Out of Range)
Function to calculate the temperature:
IF(HightByte>=0xF0)
{
Temperature= ((HightByte-0xF0)*256-LowByte)/10
}
Else
{
Temperature= ((HightByte)*256-LowByte)/10
}
Sensor Connection Diagram
As the sensor uses RS485 interface which can not be connected directly to the MCU, a MAX485 chip
will bridge the TTL interface to RS485.
For PC users, either a USB-RS485 or RS232-RS485 converter will bridge the gap.
Connect Sensor to MCU via MAX485