AJ71UC24-S2

[Raph 0]

Hi Everyone, I want to connect between Mitsubishi and Allen Bradley using Modbus Protocol. in Mitsubishi PLC, i use AJ71UC24-S2 as a slave. what confusing me was, how to initiate command and sent command in Mitsubishi PLC? like usually in modbus protocol when want to read register we use function code 3. and how to define data tag to modbus address? Thanks.

[kaare_t 155]

Hi. As long as you are a slave in the Mitsubishi you don't need to "send" any data. The module will automaticly generate the correct response when a request is received. The devices in the Mitsubishi CPU are allocated to specific Modbus devices, take a look in the manual under chapter 6.4 (Device Allocations).