Function 0X04 - Read Temperature And Humidity Value - Protech Systems SI-W509 User Manual

4.2.3 Function 0x04 – Read Temperature and Humidity Value
This function code is used to read the temperature and humiditysensor value
of SI-W509 I/O module.
Request
Offset Description
00 Slave ID address
01 Function Code
02 ~ 03 Channel address
04 ~ 05 CRC
Response-1
The channel address is 0x4640.
Offset Description
00 Slave ID address
01 Function Code
02 Byte Count
03 ~ 04 Readback value
05 ~ 06 CRC
Response-2
The channel address is 0x4650.
Offset Description
00 Slave ID address
01 Function Code
02 Byte Count
03 Readback value
04 ~ 05 CRC
Error Response
Offset Description
00 Slave ID address
01 Function Code
02 Data
03 ~ 04 CRC
SI-W509 SERIES USER MANUAL
Chapter 4 MODBUS RTU Protocol
Counts
1 Byte 1 to 255
1 Byte 0x04
2 Bytes
•
0x4640: Get Temperature Value
•
0x4650: Get Humidity Value
2 Bytes Produced by utility.
Counts
1 Byte 1 to 255
1 Byte 0x04
1 Byte 2
2 Bytes
•
Temperature Value: 0xF060
~0x30D4 (-40°C ~125°C)
2 Bytes Produced by firmware.
Counts
1 Byte 1 to 255
1 Byte 0x04
1 Byte 1
1 Bytes •
Humidity Value: 0x00~0x64
(0% ~ 100%)
2 Bytes Produced by firmware.
Counts
1 Byte 1 to 255
1 Byte 0x84
1 Byte 0xCD: No Function
2 Bytes Produced by firmware.
Data
Data
Data
Data
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