53
Connecting to the RS-232C Port at the Host Section 4-1
Connecting to a CVM1/CV-
series Host Link Unit
CVM1/CV-series Rack-mounting Unit: CV500-LK201
A CVM1/CV-series Host Link Unit (CV500-LK201) has two connectors (com-
munications ports 1 and 2). Either of these ports can be used for connection
to an NT631/NT631C by the RS-232C method. However, since the connec-
tors at these ports are of different types, a cable that matches the connector
must be prepared.
• Communications port 1
Communications port 1 is a 25-pin connector for RS-232C use only.
• Communications port 2
Communications port 2 is a 9-pin connector which allows selection of the
RS-232C or RS-422A method. When this port is used with the RS-232C
method, the I/O port selector switch on the front of the PT 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 com-
munications conditions for the CPU Bus Unit settings.
*1
Set the host link communications speed at 9600 bps or 19200 bps with the
memory switch at the NT631/NT631C. For details, refer to 6-7-2 Setting the
Host Link Method (page 155).
*2
The 1-to-N setting enables BCC (Block Check Character). It is not actually
possible to connect more than one NT631/NT631C in a single host link.
Set the CPU Bus Unit settings directly from a Programming Device (e.g. CX-
Programmer).
For details on the CPU Bus Unit settings, refer to the SYSMAC CVM1/CV-
series Host Link Unit Operation Manual (W205-E1-@).
Item Setting at Host
Communications speed
Set the same speed as set at the NT631/NT631C
(*1)
Transfer code ASCII, 7 data bits, 2 stop bits
Parity Even
1-to-1, 1-to-N
1-to-N
(*2)
Instruction level Level 1, 2, 3