Serial Configuration - Modbus; Modbus Slave - Weidmuller WI-GTWY-9 User Manual

WI-GTWY-9-xxx Wireless Gateway
passed via a repeater it will buffer this message in a queue and then forward on and wait for ACK
before it clears the buffer. If system is experiencing high radio message count and poor radio
path creating number of retries, cases could exist that the buffers will empty. Enabling the Reset
on Buffer Empty feature will reset the module and then continue to operate.

4.7 Serial Configuration - MODBUS

The WI-GTWY-9-xxx-MD1 module provides interface for Modbus Slave, Modbus Master and
Allen-Bradley DF1. This Modbus interface uses the Modbus RTU protocol - also known as the
Modbus Binary protocol. This manual assumes that the reader has a good understanding of the
Modbus or DF1 protocol.

4.7.1 MODBUS Slave

If you use the WI-GTWY-9-xxx Modbus Slave interface, then the host device will be a Modbus
Master device. The only configuration required for the Modbus slave interface is selecting the
Modbus address and serial port parameters. This is done in the "Serial Settings" screen. A valid
Modbus slave address is 1 to 255.
Each I/O register (and status register) in the WI-GTWY-9-xxx can act as one of the following
types of Modbus registers
00001-09999 = Output Coils (digital/single bit)
10001-19999 = Input Bits (digital/single bit)
30001-39999 = Input Registers (analog/16 bit)
40001-49999 = Output Registers (analog/16 bit)
For example:
• If the Modbus Master sends the WI-GTWY-9-xxx a "read" command for Modbus input
10457, then the WI-GTWY-9-xxx will respond with the value in I/O register 457.
• If the Modbus Master sends the WI-GTWY-9-xxx a "write" command for Modbus output
02650, then the WI-GTWY-9-xxx will write the value to I/O register 2650.
• If the Modbus Master sends the WI-GTWY-9-xxx a "read" command for Modbus input
30142, then the WI-GTWY-9-xxx will respond with the value in I/O register 142.
• If the Modbus Master sends the WI-GTWY-9-xxx a "write" command for Modbus output
40905, then the WI-GTWY-9-xxx will write the value to I/O register 905.
The WI-GTWY-9-xxx I/O register values are 16 bit (hexadecimal values '0000' to 'FFFF', or
decimal 0 to 65535), regardless of whether the register represents a discrete, analog or count point.
70
V1.18