User`s manual

SMG-1100/6100 Introduction
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MODBUS RTU/ASCII Master
In the MODBUS Gateway configuration for a MODBUS RTU/ASCII master and MODBUS TCP slave, the software
running on each MODBUS RTU/ASCII master device sends MODBUS RTU/ASCII request messages to the
MODBUS Gateway via its connected serial port. The MODBUS Gateway then converts the messages to MODBUS
TCP request messages and securely sends them to MODBUS TCP slaves in MODBUS TCP slave devices via the
Internet, based on slave ID values in the MODBUS request messages and settings in the MODBUS Gateway.
After the slave devices receive MODBUS TCP request messages, they reply with MODBUS TCP response
messages to the MODBUS Gateway. Once the MODBUS Gateway receives MODBUS TCP response messages,
they are converted to MODBUS RTU/ASCII response messages and sent to the corresponding MODBUS
RTU/ASCII master device.
Managing MODBUS Gateway
After the MODBUS Gateway application for each serial port is determined, the configuration of MODBUS
Gateway can be set up via SMG Manager. Refer to MODBUS section for detailed MODBUS Gateway configuration
instructions.