VA-4 - Connecting the VA-4 9
Figure 4: Crossed Cable RS-232 Connection
Hardware flow control is not required for this unit. In the rare case where a
controller requires hardware flow control, short pin 1 to 7 and 8, and pin 4 to 6 on
the controller side.
Method B (
Figure 5)—Connect the RS-232 9-pin D-sub port on the unit via a
straight (flat) cable to the null-modem adapter, and connect the null-modem
adapter to the RS-232 9-pin D-sub port on the PC. The straight cable usually
contains all nine wires for a full connection of the D-sub connector. Because the
null-modem adapter (which already includes the flow control jumpering described
in Method A above) only requires pins 2, 3 and 5 to be connected, you are free to
decide whether to connect only these 3 pins or all 9 pins.
Figure 5: Straight Cable RS-232 Connection with a Null Modem Adapter
1
2
6
3
7
4
8
5
9
1
2
6
3
7
4
8
5
9
PC
1
2
6
3
7
4
8
5
9
to PC
Null-Modem
Adapter