ganutenator
Lifetime Supporting Member
I'm looking to create a modbus rtu fuction block master in codesys or structured text.
I could devote an entire thread to the why. Not trying to defend this protocol. My basic why: modbus is the built in protocol, cost.
Because it is slow, It would need to cycle through reads and writes w/ dif. priority levels. i.e. a new data value change for a vfd speed coming up would be a priority 2.
I would want it to report back communication errors.
I would want it to be editable for the number of devices and corresponding modbus addresses and address locations. i.e. altivar 212 vs an alitvar 340 for example.
This is nearly above my ability. I could do it given enough time.
My platform is the Schneider M340, So Machine 251, Wago (forgot the model, it at work) plc.
How could I make this a community based project and/if enough people could use such a function.
I could devote an entire thread to the why. Not trying to defend this protocol. My basic why: modbus is the built in protocol, cost.
Because it is slow, It would need to cycle through reads and writes w/ dif. priority levels. i.e. a new data value change for a vfd speed coming up would be a priority 2.
I would want it to report back communication errors.
I would want it to be editable for the number of devices and corresponding modbus addresses and address locations. i.e. altivar 212 vs an alitvar 340 for example.
This is nearly above my ability. I could do it given enough time.
My platform is the Schneider M340, So Machine 251, Wago (forgot the model, it at work) plc.
How could I make this a community based project and/if enough people could use such a function.
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