RLE LD5000 - Manual (Page 82)

Appendix A: Modbus Communication User Guide: LD5000
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A-4 RTU FRAMING
The example below shows a typical Query/Response from a LD5000 module.
Table 11: Query Sample
Slave
Address
Function
Code
Count
Bytes of
Data
Register
Data
Msb Lsb
Register
Data
Msb Lsb
Register
Data
Msb Lsb
CRC 16
“Lsb”
CRC
16”Msb”
02 04 06 00 00 00 00 00 01 B5 A3
Table 12: Response Sample
Slave
Address
Function
Code
Count
Bytes of
Data
Register
Data
Msb Lsb
Register
Data
Msb Lsb
Register
Data
Msb Lsb
CRC 16
“Lsb”
CRC
16”Msb”
02 04 06 00 00 00 00 00 01 B5 A3
• Slave address 2 responds to Function Code 4 with 6 bytes of hexadecimal data and ends with CRC16 checksum.
Register Values:
40001 = 0000 (hex)
40002 = 0000 (hex)
40003 = 0001 (hex)
A-5 LD5000 LCD MODBUS STATUS SCREEN (COMMS)
Adr:xxx - The Modbus slave address set by the dip switch #1
9600b - The current baud rate of the Modbus RS-485 port
4in:xxxxx out:xxxxx - The number of RS-485 bytes received and transmitted
Min:xxxxx out:xxxxx - The number of Modbus packets received and transmitted
RESET - Press the Enter ( ↵) key to reset the Modbus counters
Modbus Adr:002 9600b
4in:18234 out:12214
Min:3345 out:2121
->RESET