w4tsn / node-red-contrib-modbus-api

An API like node-red implementation of the modbus-serial package.
BSD 3-Clause "New" or "Revised" License
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Possibility for multiple registers in one modbus in node #26

Open SteffenWG opened 1 year ago

SteffenWG commented 1 year ago

Problem: Modbus clients asks for registers between registers that you specify. Lets say a client is set to ask for holding register 50, 51 and 52. Then the next registers is 70, 71 and 72. The client will ask also for all the registers between 52 and 70. (At least the OPC kepserver does.) I understand that this is normal behaviour. In a typical modbus driver/server it will just respond with 0 if it is not set to that specific register. It seems that in the modbus api solution this is not happening. The client complaints and node-red modbus api spits out that a client is requesting an invalid register.

Solution: A solution could be that the modbus in node in the Register field you could specify 53-69. That way that node would be triggered if a client specifies any of those registers.