Omron SYSMAC CS1W-SCB41-V1 User Manual

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SECTION 9
Using Modbus-RTU Slave Mode (Unit Version 1.3 or Later)
This section describes the procedure and other information required to use Modbus-RTU slave mode.
9-1 Modbus-RTU Slave System . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 274
9-1-1 Communicating with CS/CJ-series CPU Units Using Modbus . . . . 274
9-2 Setup Area Allocations (Modbus-RTU Slave Mode) . . . . . . . . . . . . . . . . . . . 275
9-2-1 Setup Area Words . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 275
9-2-2 Setup Area Contents . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 277
9-3 Auxiliary Area and CIO Area Allocations (Modbus-RTU Slave Mode) . . . . 278
9-3-1 Auxiliary Area Allocations. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 278
9-3-2 CIO Area Allocations . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 279
9-3-3 Supported Modbus-RTU Commands . . . . . . . . . . . . . . . . . . . . . . . . 283
9-3-4 Command and Response Details . . . . . . . . . . . . . . . . . . . . . . . . . . . 283
9-4 Communications Timing. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 290
9-4-1 Simultaneous Commands and Communications Ports. . . . . . . . . . . 290
9-4-2 Communications Control Signals and Communications Timing . . . 291
9-4-3 Flags for Network Communications. . . . . . . . . . . . . . . . . . . . . . . . . 291
9-4-4 Timing of Commands Addressed to a Host Computer. . . . . . . . . . . 293
9-4-5 Reception Buffers . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 295
9-4-6 Error Responses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 295
9-5 Changes from Previous Products . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 295
9-5-1 RS-232C Ports . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 295
9-5-2 RS-422A/485 Ports. . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 297
9-6 Modbus-RTU Slave Function for Replacing Existing PLCs . . . . . . . . . . . . . 298
9-6-1 Support for 1:1 Modbus-RTU Slave . . . . . . . . . . . . . . . . . . . . . . . . . 298
9-6-2 Modbus-RTU Slave-compatible Device Selection . . . . . . . . . . . . . . 299

Omron SYSMAC CS1W-SCB41-V1 Specifications

General

Brand	Omron
Model	SYSMAC CS1W-SCB41-V1
Category	Network Hardware
Language	English