Legend 100CD  (250-0407)  Modem Diagram and Settings   Faxback Doc. # 15019

Common IRQ assignments for COM1 to COM4 ports are:

      COM Port         IRQ

         1              4
         2              3
         3              4
         4              3

Since IRQs can not be shared at the same time, it is recommended to
configure COM3 to use IRQ5, or COM4 to use IRQ2.  This avoids sharing of
IRQs with COM1 and COM2.

To change the default COM Port or IRQ settings from COM1/IRQ4 to another
setting, locate the Switch Block SW-1 on your internal modem.

                Switch Block SW-1 Location
             ┌────────────────────────────────┐
             │ O o         ┌───┐              ├──┐
             │             │   │              │┌─┘
             │  ┌────┐     └───┘          ┌───┤│
             │  │    │                    ├┬──┤│
             │  └────┘                    ├┴──┤│             SW-1
             │                      ┌─┐   └┬──┤│        ┌─────────────┐
             │                      │ │   ┌┴──┤│      ┌─┤┌─┬─┬─┬─┬─┬─┐│
             │  ┌───┐               └─┘   └───┤│      │ │├┬┼┬┼┬┼┬┼┬┼┬┤│
             │  └───┘                     ┌───┤│      │ │└┴┴┴┴┴┴┴┴┴┴┴┘│
             │  ┌──────┐                  │   ││<─────┘ │ 1 2 3 4 5 6 │
             │  └──────┘                  └───┤│        └─────────────┘
             └──┬┬┬┬┬┬┬┬┬┬┬┬┬┬┬┬┬┬┬┬┬┬┬┬┬┬────┤│
                └┴┴┴┴┴┴┴┴┴┴┴┴┴┴┴┴┴┴┴┴┴┴┴┴┘    └┘

┌────────────┬─────┬───────┬───────┬───────┬───────┬───────┬───────┐
│  COM Port  │ IRQ │ SW1-1 │ SW1-2 │ SW1-3 │ SW1-4 │ SW1-5 │ SW1-6 │
├────────────┼─────┼───────┼───────┼───────┼───────┴───────┼───────┤
│1 (default) │  4  │  ON   │  ON   │  OFF  │  OFF     ON   │  OFF  │
├────────────┼─────┼───────┼───────┼───────┼───────────────┼───────┤
│     2      │  3  │  OFF  │  ON   │  OFF  │  ON      OFF  │  OFF  │
├────────────┼─────┼───────┼───────┼───────┼───────────────┼───────┤
│     3      │  5  │  ON   │  OFF  │  OFF  │  OFF     OFF  │  ON   │
│            ├─────┼───────┼───────┼───────┼───────────────┼───────┤
│            │  4* │  ON   │  OFF  │  OFF  │  OFF     ON   │  OFF  │
├────────────┼─────┼───────┼───────┼───────┼───────────────┼───────┤
│     4      │  2  │  OFF  │  OFF  │  ON   │  OFF     OFF  │  OFF  │
│            ├─────┼───────┼───────┼───────┼───────────────┼───────┤
│            │  3* │  OFF  │  OFF  │  OFF  │  ON      OFF  │  OFF  │
└────────────┴─────┴───────┴───────┴───────┴───────────────┴───────┘

*Use these IRQs only if your software can not address IRQ5 or IRQ2.


(ALL-04/19/95)