Omron SYSMAC CJ1W-SCU21-V1, Руководство по эксплуатации

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Specifications Section 1-6
1-6-3 Protocol Specifications
Host Link Specifications
Note 1. Confirm the baud rates and communications distance supported by con-
nected devices.
2. 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.
Item Description
Communications mode Half-duplex (Full-duplex for slave-initiated communications)
Synchronous mode Start-stop synchronization (asynchronous mode)
Baud rate (see note 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 bps
Default setting: 9,600 bps
Communications
distance (see note 1) RS-232C port: 15 m max. (see note 2)
RS-442A/485 port: 500 m max. (The total combined cable length is 500 m max. T-branch lines
must be a maximum of 10 m long.)
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 FINS c 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 PLC C-mode commands 1:1 or 1:N communications with directly connected
PLCs (The specified frame format must be prepared
on the host computer and then sent.)
FINS commands (in
Host Link protocol) 1:1 or 1:N communications with directly connected
PLCs.
PLC to host
computer FINS commands (in
Host Link protocol) Communications using SEND(090), RECV(098),
and CMND(490) from CPU Unit.
The host computer must interpret the commands
and return a response in the correct format.
Connection between the host computer and PLC
must be 1:1.