2500 XL  (250-4074)                Parallel             Faxback Doc. # 1155

OPENING THE COMPUTER

CAUTION: Static electricity can damage electronic components in a computer. 
Before opening the computer, discharge any accumulated static electricity from 
your body by touching a grounded metal object. Also, turn the computer off and 
disconnect all electrical cables from the computer.

To open the system unit, follow these steps:

1. Remove the two fastening screws from the computer's outer cover. These 
   screws are located at the sides of the cover, near the back of the unit.

2. Slide the cover toward the front of the computer until it clears the 
   alignment pin.

3. Lift the cover off the computer.

4. Unlock the keylock, if necessary.

5. Turn the fastener on the expansion adapter cover with a coin or a
   screwdriver. The fastener pops up slightly after one-quarter turn.

6. Remove the expansion adapter cover by pulling it out of the retaining slots
   at the bottom of the frame.

7. Rotate the carriage away from the frame. The carriage should rest at a
   90-degree angle in the slots on the frame.

CLOSING THE COMPUTER

Follow these steps to close the computer:

1. Close the carriage. Be sure it rests securely against the center bar.
   Check that any connections between the carriage and the main logic board
   are intact.

2. Slide the tabs at the bottom of the expansion adapter cover into the
   retaining slots on the frame.

3. Close the expansion adapter cover. Be sure it rests securely over the
   center bar.

4. Securely tighten the two fasteners on the expansion adapter cover.

5. Carefully position the outer cover on the base.

6. Slide the cover over the base toward the back of the computer until it fits
   into place.

7. Screw the two cover mounting screws into the outer cover of the computer.

INSTALLING A PARALLEL DEVICE

The 25-pin parallel port is located on the back of your computer. See the 
"Hardware Setup" section to connect a parallel device.

The parallel port on your computer allows either one-way or two-way data 
transfer:

* Unidirectional (one-way). The computer uses the port only to send output to 
  the parallel device. It does not receive input through the port.

* Bidirectional (two-way). The computer the port to send output to the 
  parallel device and to receive input from the device.

Run the Setup utility on the Startup and Operating Diskette to configure the 
parallel port for unidirectional or bidirectional operation.