Setting registers in DF MB TCP Slave


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I have a ethernet server device running MB TCP in DF, and am able to read the registers OK using QuickMod as MB client, but am unable to set registers from QuickMod. See attached screen shot for error message.

The server DF and QuickMod are running as separate instances on same machine, and I have DF Pro license on USB hardware key.

1. Are there any read/write limitations on channels that have a MB slave address?

2. Can I have 2 channels with same MB slave address, 1 for reading, 1 for writing (since I have to do this in channels to talk to MB slave (DF as client) I figured it would be the same for MB slave)

If this should work, do you have any troubleshooting tips?




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For reasons I'm not completely sure of, it looks like DF is currently compiled up to only support function 16 for output, which means you can only do multiple registers at a time, or floats. Actually I think you can do single registers, but you have to use 16. You can do this from a DF you create by selecting the Set Register (16) command instead of (6). However, I'm not sure if quick mod exposes this command.

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How could you read the registers? i have two problem, first one is that i can't set the registers with any value in program. i can't see in the watch screen if they get the value?

And the second one is i can't read the registers in the same computer via QuickMod. i'm trying to read only one register but it's allways turning timeout.

i'm using port 502 and ip is the PCs ip. and i set the modbus tcp device as server. So can you help me what should i do?

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thank you, actually i'm using the serial modbus also, so i'm reading some tempreture values from serial(modbus RTU) and than try to share it via Modbus tcp.. so there is two device one is for serial communication one is for tcp structure..

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