4

CJ1W-SCU

Protocol Specifications

Host Link Specifications

*1. Confirm the baud rates and communications distance supported by connected devices.

*2. The CJ1W-SCU

@2 is required for communications at 230,400 bps.

*3. The maximum cable length for RS-232C is 15 m. The RS-232C standard, however, does not cover baud rates above 19.2 Kbps. Refer to the

manual for the device being connected to confirm support.

*4. The specified frame format must be prepared on the host computer and then sent.

*5. The host computer must interpret the commands and return a response in the correct format.

Connection between the host computer and Controller must be 1:1.

Protocol Macro Function Specifications

Item

Description

Communications mode

Half-duplex (Full-duplex for slave-initiated communications)

Synchronous mode

Start-stop synchronization (asynchronous mode)

Baud rate *1

RS-232C port and RS-422A/485 ports:

1,200/2,400/4,800/9,600/19,200/38,400/57,600/115,200/230,400 bps *2

Default setting: 9,600 bps

Communications distance

*1

RS-232C port

: 15 m max. *3

RS-422A/485 Port :

• CJ1W-SCU

@1-V1

500 m max. (total cable length: 500 m max., T-branch branch lines: 10 m max.)

• CJ1W-SCU

@2

1,200 m max. (total cable length: 1,200 m max., Multidrop connections are possible. However, maximum cable length is 500 m if

the NT-AL001 is used for RS-422A-485 connections.)

Connection configuration

RS-232C port

: 1:1 (1:N (N = 32 Units max.) is possible using an Converting Link Adapters.)

RS-422A/485 port : 1:N (N = 32 Units max.)

Number of connected Units

32 Units max. (unit numbers 0 to 31; unit number 0 is set for 1:1 connection)

Frame structure

C-mode commands

Header: @, address: (host link unit number) 0 to 31 (BCD), data: header code + text, error check

code: FCS, terminator: * +CR

FINS commands

Header: @, address: (host link unit number) 0 to 31 (BCD), data: header code (always “FA”) + FINS

header + FINS command + text, error check code: FCS, terminator: * +CR

Error check codes

Vertical parity: Even, odd. or none

FCS (horizontal parity converted to ASCII)

Command flow and support

Command flow

Commands

Contents

Host computer to Controller

C-mode commands

1:1 or 1:N communications with directly connected Controller *4

FINS commands

(in Host Link protocol)

1:1 or 1:N communications with directly connected Controller.

Controller to host computer

FINS commands

(in Host Link protocol)

Communications using SEND(090), RECV(098), and CMND(490) from CPU

Unit. *5

Item

Description

Number of protocols

20 max.

Can be created and registered with the Protocol Support Tool (CX-Protocol).

Number of sequences

1,000 max.

Per protocol

Number of sequences

60 max.

Number of messages

300 max.

Number of reception

matrixes

100 max.

Sequence execution condition

Using the CPU Unit’s PMCR (260) instruction (specifying the sequence number)

Communications mode

Half-duplex or full-duplex

Synchronous mode

Start-stop synchronization (asynchronous mode)

Baud rate *1

RS-232C port and RS-422A/485 ports:

1,200/2,400/4,800/9,600/19,200/38,400/57,600/115,200/230,400 bps

Default setting: 9,600 bps *2

Communications distance *1

RS-232C port

: 15 m max.

RS-422A/485 port :

• CJ1W-SCU

@1-V1

500 m max. (total cable length: 500 m max., T-branch branch lines: 10 m max.)

• CJ1W-SCU

@2

1,200 m max. (total cable length: 1,200 m max., Multidrop connections are possible. However, max-

imum cable length is 500 m if the NT-AL001 is used for RS-422A-485 connections.)

Connection configuration

RS-232C port

: 1:1 (1:N (N = 32 Units max.) is possible using a Converting Link Adapter.)

RS-422A/485 port : 1:N (N = 32 Units max.)

Number of connected Units

32 Units max. (unit numbers 0 to 31; unit number 0 is set for 1:1 connection)

Maximum number of data

exchange words between

Controller and protocol

macro function

Operand setting

250 words

Including the word that specifies the number of

words (1 word)

Link word setting

500 words

O1, O2, I1, and I2: 500 words total

Direct setting

500 words

Maximum number of words per data attribute