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CMB27 / ModbusRTUSlave

This is an Arduino library that implements the slave/server logic of the Modbus RTU protocol.
MIT License
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Exception response codes #17

Closed rob040 closed 1 year ago

rob040 commented 1 year ago

What Exception response codes have you defined? They do not appear conforming to the Modbus spec. The library sourcecode uses magic values, but that keeps them unexplained.

CMB27 commented 1 year ago

I based the exception response codes on MODBUS Application Protocol Specification V1.1b3 for the function codes that this library supports, which are noted in the README. I believe these are only function codes 1, 2, 3, and 4.

If you have found a discrepancy between the code and the specification, please indicate the lines of code in which the discrepancy occurs and the relevant document and page of the specification.