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AC7A/B User’s Guide
CONNECTING THE AC7A/B TO A PC OR OTHER RS-232 DEVICE
A standard RS-232 serial cable may be used to connect the AC7A/B adapter card to the PC. One end of the RS-232
cable must have a male 25-pin (DB-25) connector for the AC7A/B. The other end of the cable is for the PC, and will
most likely need either a 9-pin (DB-9) female connector, or a 25-pin (DB-25) female connector, depending on your
computer. Figure 3-3 shows the connections between a 25-pin RS-232 serial port and the AC7A/B using a standard
straight-through cable. Figure 3-4 shows the connections between an AC7A/B adapter card and a 9-pin RS-232
serial port using a standard straight-through cable.
Figure 3-3: Standard Straight-Through 25-Pin to 25-Pin RS-232 Cable
Figure 3-4: Standard Straight-Through 9-Pin to 25-Pin RS-232 Cable
It is also possible to make your own cable for connections between the AC7A/B and an RS-232 device. The only
connections that are absolutely necessary are transmit and receive (RS-232 pins 2 and 3) and signal ground, which
is pin 7 of standard 25-pin connectors. Ground is usually pin 5 on 9-pin RS-232 connectors. (Note: the 9-pin
connector on the AC7A/B adapter card is for RS-422/485, not RS-232.)
INSTALLATION (cont.)
