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4-1
Section
Connecting to the RS-232C Port at the Host
43
od, the I/O port selector switch on the front of the Unit must be set to RS-232C
(the upper position).
CPU Bus Unit Settings
When connecting to a CVM1/CV-series Host Link Unit, set the following commu-
nication conditions for the CPU Bus Unit settings.
Item
Setting at Host
Baud rate
Set the same baud rate as set at the NT21
(*1)
Transfer code
ASCII, 7 data bits, 2 stop bits
Parity
Even
1-to-1, 1-to-N
1-to-N
(*2)
Command level
Level 1, 2, 3
*1 Set the Host Link baud rate at 9,600 bps or 19,200 bps with the memory switch
at the NT21. For details, refer to Setting the Host Link Method (page127).
*2 The 1-to-N setting enables BCC (Block Check Character). It is not actually
possible to connect more than one NT21 in a single Host Link.
Set the CPU Bus Unit settings directly from a Programming Device (e.g., SYS-
MAC Support Software).
For details on the CPU Bus Unit settings, refer to the SYSMAC CVM1/CV-series
Host Link Unit Operation Manual (W205-E1-
j
).
Setting the Front Switches
RS-232C
Communications port 1
(RS-232C)
Communications port 2
(RS-232C/RS-422A)
I/O port selector switch
RS-422A
@
Unit # (SW3, SW4)
When using communication port 2, set these
switches to 0.
@
Communication condition setting (Pin 1)
Set this pin to OFF.
Communication is executed in accordance with the
CPU Bus Unit system settings made at the PC. The
initial values for the system settings are as follows.
- Baud rate: 9,600 bps
- Parity: Even
- Xon/Xoff control: Not executed
- Communication method: Full duplex
- Stop bits: 2 stop bits
- Data length: 7 bits
@
I/O port selection (selector switch)
Set this to RS-232C.
@
CTS selection (Pins 2 and 3)
Set pin 2 or 3 to ON. (Set this always to 0V.)
To use communication port 1, turn ON pin 2. To use
communication port 2, turn ON pin 3.
Connecting to a CS/CJ-series Serial Communications Unit
CS/CJ-series Rack-mounted Unit: CS1W-SCU21
CJ-series: CJ1W-SCU41 (Port 2 is an RS-232C Port.)
Setting the Front Switches
Set the unit number of the Serial Communications Unit by using the rotary switch