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Hi,
I am trying to use Machine Expert on a M241 for writing to a modbus serial RTU (RS485) device. I am trying to use the Modbus_IOScanner and Generic Modbus Slave. For reading it works fine (I am using Cyclic as the trigger it is ok), but for writing I would like to use the Application trigger. The documentation is very vague in terms of how to use it (https://content.helpme-codesys.com/en/CODESYS%20Modbus/_mod_edt_slave_com_channel.html ) this is what it mentions:
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Application: The Modbus request is triggered by the PLC application. This happens by means of the ModbusChannel function block, which is included in the respective I/O driver library. This function block provides complete control of and information about the execution of this command, for example the start time, the processing time, and the result.
So I followed the step by step, but the ModbusChannel part does not work
When I try to use the ModbusChannel it asks for a slave (ModbusSlaveComPort type), how do I get an instance of this? If I try to pass the Generic Modbus Slave device variable name SERIAL_POWER_METER it does not work (type does match)
On Wago similar concept works: https://www.wago.community/t/codesys-modbus-rtu-when-are-values-read/1253/2
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