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5-1
Section
Connecting to the Host’s RS-422A/485 Port
73
the communications mode switch to select 4-wire (RS-422A) communications
and turn ON the terminator switch to enable the terminating resistance.
Unit number switch
Set the unit number between 0 and F
so that it will not duplicate the
numbers used in other Units.
Terminator switch
Turn ON to connect the terminator.
(Set terminator ON.)
Communications mode switch
Set the 2-wire/4-wire selector switch to
“4” to select 4-wire (RS-422A)
communications.
Allocation DM Area Settings for CPU Unit
Settings are written from the Programming Device (a Programming Console or
CX-Programmer) directly into the allocated DM Area (PC Setup) of the CPU
Unit. After the settings are written, they become effective by turning the power
ON, restarting the Unit, restarting the communication port, or execution of the
STUP instruction.
The following table shows the words allocated in the DM Area and the settings.
m = D 100
×
unit number
Allocated DM word
Value
Settings
Port 1
Value
Settings
m
8000
Host Link mode, 2 stop bits, even parity, data
length 7 bits
m+1
0000
Baud rate 9,600 bps.
m+1
0007
Baud rate 19,200 bps.
m+2
0000
Transmit delay time 0 ms.
m+3
0000
No CTS control Unit No.0 for Host Link
Connecting to a CPU Unit
CVM1/CV-series (-EV
j
) CPU Units
CVM1-CPU01-EV2/CVM1-CPU11-EV2/CVM1-CPU21-EV2
PC Setup
When connecting to a CVM1/CV-series CPU Unit, set the following communica-
tion conditions for the PC Setup.
Item
Setting at Host
Baud rate
Set the same baud rate as for the NT21.
(*1)
Stop bits
2 stop bits
Parity
Even
Data length
ASCII 7 bits
Unit #
00
*1 Set the Host Link baud rate at 9,600 bps or 19,200 bps with the Comm. Speed
memory switch at the NT21. For details, refer to Setting the Host Link Method
(page 125).
Set the PC Setup directly from a Programming Device (e.g., SYSMAC Support
Software).
For details on the PC Setup, refer to the SYSMAC CVM1/CV500/CV1000/
CV2000 Operation Manual: Ladder Diagrams (W202-E1-
j
).