Instruction Manual

PPC-2000 User’s Guide Appendix A: Modbus Protocol
Doc.# 30002-00 Rev 2.3 Watlow Anafaze 281
Write Examples
The data written is echoed back to the controller. The following
table displays information for sample packet for host
transmission. Table A.5 shows the query and Table A.6 shows
the response.
Table A.5 Sample Packet for Host Query
Table A.6 Sample Packet for Slave Response
Example
Slave
Address
Function
Address
High
Address
Low
Data
High
Data
Low
CRC
Writing loop 1 PB
(20), controller 4
(single point write)
04 06 0C 1C 00 14 4B 06
Writing digital
output 30 (on),
controller 2
(single coil write)
02 05 0B D5 FF 00 9F D5
Example
Slave
Address
Function
Address
High
Address
Low
Data
High
Data
Low
CRC
Writing loop 1 PB
(20),
controller 4
(single point write)
04 06 0C 1C 00 14 4B 06
Writing digital out-
put 30 (on), con-
troller 2 (single
coil write)
02 05 0B D5 FF 00 9F D5