Some common issues that may arise with Modbus Slave Registration Keys include:
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Some industrial gateways support a feature where remote slaves actively connect to a central master. To prevent unauthorized devices from registering as slaves, a "Registration Key" (often a simple string or integer) is configured on both the slave and the master. The slave sends this key in a proprietary Modbus request (often function code 0x5A or similar vendor-specific codes). Some common issues that may arise with Modbus