If you install two option cards with parallel ports, designate one as the primary port and the other as the secondary port. In this ease, you need co set switches 1 and 2 ON to disable the built-in port.

Note

If MS-DOS searches the system for a parallel port and finds

only one, it names it LPT1. If there are two parallel ports, it names the primary port LPT1 and the secondary LPT2.

Switches 3 and 4 (serial port)—tell the computer how co access the built-in serial port.

The built-in serial port functions as either the primary or secondary serial port. If you install an option card with its own serial port, you must set these two DIP switches so there is no conflict between the built-in port and the additional port. Here are some examples:

If you install an option card with a serial port pre-set as primary by the manufacturer, you must designate it as the primary port and make the built-in port the secondary port.

If you install an option card or peripheral with a serial port not pre-set, you must designate it as the secondary serial port and the built-in port as the primary serial port.

If you install two option cards with serial ports, designate one as the primary port and the other as the secondary port. In this ease, you need to set switch 4 on to disable the built-in port; it doesn’t matter whether switch 3 is ON or OFF.

Note

If MS-DOS searches the system for a serial port and findsonly one, it names it COM1. If there are two serial ports, itnames the primary port COM1 and the secondary COM2.

Changing DIP Switches and Using Setup

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