Hi everyone,

I'm trying to stablish a modbus RTU comunication Master-Slave, the hardware as follow:

CPU1214 AC/DC/Rly

CM 1241 (RS422/485) 1CH32-0XB0 firmware choosen in hardware configuration is V2.0

Ekor RPG relay Ormazabal

The problem that I have is, altough I see that the comunication chanel is ok when configured I don't recieve any kind of data. The TX Led indicator on CM is always flashing orange and when i call de MB_MASTER that also is selected a V2.0 version. Busy indicator of the FB always is activated because I'm using system flag for 5Hz to make a Request to the Slave, and the Error bit and Status byte form the function block always are 0000.

Best Regards,

Hello,

problem can be not simple. You need set same communiaction settings for both devices, correct cable wiring, propper terminating, propper Slave address, Data address set, right Buffer due your needed data set. Did you see general info about Modbus RTU? Look to Smiffy first post where he post important general infos. You can also simulate your real device with PC MB Slave application to see what is happening.