I need it to be real-time like our normal PLC I/O's. Well, I've tried to switch the Read/Write Function codes in high speed that's why they are jamming. I've tried to put some gap using Shift Register and it worked, but still slow. Anyway, I've just decided to use basic I/O's for control then Modbus for monitoring (basic status and position feedback). Thank you very much.
What do you mean by fast transactions? What sort of speeds are you expecting with modbus Serial?
There is no need for the data to be jamming like a party if the code is executed correctly.
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