HP 24SII manual

If you are interfacing a DTE device to the Model 24SII DES (DCE), you must use a one-to-one or straight cable as shown in Figure 5 on the following page. If you are interfacing a DCE device to the Model 24SII DES (DCE), you must use a crossed cable as shown in Figure 6 on the following page.

When using XON/XOFF protocol, it may be desirable to use cables with only Tx, Rx and GND connected. On the serial ports of a BayTech Model 24SII DES, input handshaking lines are enabled if nothing is connected, allowing the system to operate with only Tx, Rx and GND connected.

CAUTION: Do not attempt to use a serial cable on a parallel port. Since an EIA-232 serial port usually carries a potential of +12 and -12 volts, plugging a serial cable from that port into a parallel port may cause damage to the parallel port.

￿￿