the connections for these standard interfaces are made through the db25s connector on the rear panel. for all rs-232 input and output signals, the printer follows both the electronics industries association’s (eia) rs-232 specifications and the consultative committee for international telegraph and telephone (ccitt) v.24 standard signal level specifications.

    table 2 shows the pin configuration and function of the rear panel serial data connector on the printer.

   

   

    rs-232 interconnections

    the printer is configured as data terminal equipment (dte).

    figure 38 illustrates the internal connections of the printer’s rs-232 connector.

    figure 39 illustrates the connections required to interconnect the printer with the standard 9-pin serial port connector on a computer.

    if using a 9-pin to 25-pin adapter plug attached to the computer, use a null modem cable between the adapter plug and the printer.

    to connect the printer to other dte devices with db25 connectors (such as the serial port of a pc), an rs-232 null modem (crossover) cable should be used.

   

    when the printer is connected via its rs-232 interface to data communication equipment (dce) such as a modem, use a standard rs-232 (straight-through) interface cable. figure 40 illustrates the connections required for this cable.

   

   

    rs-422/rs-485 interconnections

    the printer may be connected to a host computer by either an rs-422 or an rs-485 interface. the db25 connector on the rear of the printer uses specific pins for this purpose. figure 41 illustrates the required cable wiring for interconnecting to the printer’s db25 connector. figure 42 illustrates the internal connections of the printer’s rs-422 or rs-485 connector.