Hi all,
No burnt or loose connections today so I got to spend some time on my latest pet project.
I have a Modbus RTU slave (Shinko DCL-33A temp controller) that does not support multiple register access. I'm assuming I have to send all 40 odd parameters one message[parameter] at a time as a broadcast using address 0? (At the moment I am only talking to one. However the project will finish up with 8.)
I've never had a decent chance to sit down with Step 7 until today but I managed to fumble through and get the PLC to successfully send the SV to the DCL-33A. (Just to let you know where my knowledge is at.)
Seems like a lot of Indexed type of instructions to dump 40 odd parameters into the DCL-33A? I'm thinking I can set up a DB called "SEND_DCL_PARA" with all the controller parameters stored in a logical order (all accessible (R/W) from my HMI) and have a word reserved for the SEND FC data byte offset. After a successful transmission the offset is increased by another 4 byte's to send the next data group. Is the method how it's generally achieved?
I appreciate your guidance.
No burnt or loose connections today so I got to spend some time on my latest pet project.
I have a Modbus RTU slave (Shinko DCL-33A temp controller) that does not support multiple register access. I'm assuming I have to send all 40 odd parameters one message[parameter] at a time as a broadcast using address 0? (At the moment I am only talking to one. However the project will finish up with 8.)
I've never had a decent chance to sit down with Step 7 until today but I managed to fumble through and get the PLC to successfully send the SV to the DCL-33A. (Just to let you know where my knowledge is at.)
Seems like a lot of Indexed type of instructions to dump 40 odd parameters into the DCL-33A? I'm thinking I can set up a DB called "SEND_DCL_PARA" with all the controller parameters stored in a logical order (all accessible (R/W) from my HMI) and have a word reserved for the SEND FC data byte offset. After a successful transmission the offset is increased by another 4 byte's to send the next data group. Is the method how it's generally achieved?
I appreciate your guidance.
Last edited:
