Hard Disk Controller  (250-4058)  Installation          Faxback Doc. # 5529

If you have any doubts about your ability to install this option board have
the service technicians at your Radio Shack Service Center install it for
you. As mentioned earlier, touch a grounded object before you work with the
PC boards. Also remember that your hard drive(s) must be installed first.

HARDWARE INSTALLATION

Please read these instructions carefully before you begin.

REMOVING THE COVER

1. Be sure your computer is turned off.

2. Be sure that the power to all system's peripheral devices (modem,
   printer, monitor, and so on) is also switched off.

3. Unplug the computer's power cord from the wall.

4. Note the connections of all cables from any peripheral devices, and then
   disconnect them from the computer.

5. Remove the computer cover.

6. Find the expansion slot you intend to use. Remove the blank metal
   bracket from the back of the case. Do this by removing the screw that
   holds the bracket in place and then lifting the bracket out. Save it
   for possible future use. Also save the screw, so you can fasten the new
   controller board in place.

The cover removal procedure is illustrated in the Installation and
Operation Manual supplied with your computer.

NOTE: On some early model Tandy 3000's, the fan filter might get in the way
when you try to remove the cover. To remove the filter, unfasten the Velcro
tab that holds it in place, (You can find that tab underneath the left side
of the front of the computer.) Pull down on the tab to slide the filter
out. Be sure to replace the fan filter after you complete the installation.

PREPARING THE HARD DISK CONTROLLER BOARD

Generally, it is best to locate the hard drive controller board in the
expansion slot closest to the drives.

Be sure to handle the controller board by its ends. Some of the chips are
static sensitive.

1. Check the jumper settings.

A jumper is used to complete a circuit. Notice that the hard drive 
controller board has several jumper circuits. (Look for small pins 
extending from the board, some of them connected with the jumper
connector.)

Jumpers should already be set as per Faxback Document # 5530.

If the jumper connections are incorrect, reposition the jumper connectors.

2. Be sure that your drives have been properly installed. Refer to your
   Installation Manual for instructions.

If your system contains more than one hard drive, be sure that you have set
the drives to their correct Drive Select and Drive Termination status. Your
hard disk drives include either Drive Select Pins and a Terminator Resistor
or Drive Select/Termination switches. For the proper settings. refer to
your Hard Drive Installation Manual.

INSTALLING THE CONTROLLER CABLE

1. Attach the appropriate end  of the 34-pin hard disk controller cable to
   J1 on the controller board. The connections have been keyed to fit only
   one way. If you have problems making the connection, align the key and
   try again.

To find J1 (the 34-pin connector on the controller board), refer back to 
the jumper location map.

2. Connect the other end of the 34-pin hard drive controller cable to the 
   hard drive(s). The last connector on the cable is for the secondary 
   drive, while the connector just before it is for the primary drive.

If you have only one drive in your system, use the next-to-the-last 
connector, not the last one.

INSTALLING THE DATA CABLE

1. Data Cable Installation: Attach the 20-pin hard disk data cable to its
   designated 20-pin connector on the hard disk controller board. Notice
   that this connector is also keyed.

For your primary hard drive (Drive C or 1), connect a data cable between
the 20-pin connector on the hard disk controller board labeled J2 and the
drive. Remember no to force the keyed connection.

2. If you system contains a secondary hard drive, connect a data cable for
   it.

Attach the 20-pin data connector between J3 and the secondary hard drive
(Drive D or 2). Then, attach the cable to the controller board before you
connect it to the drive.

SECURING THE CONTROLLER BOARD

1. Insert the controller board into the expansion slot sockets. Press down
   gently on both ends of the board to ensure that it is seated properly.
   Secure the board by replacing the screw that held the metal bracket in
   place (Step #3).

2. If you didn't connect the 4-pin power cable(s)  to your drive(s) during
   the drive installation, do so now. These power cables are identical and 
   can be connected interchangeably to any internal disk drives.

3. Reconnect the main power cable connector to the main logic board.

4. After all internal cables are properly connected, replace the cover. Be
   sure to replace the fan filter if you previously removed it.

5. Reconnect all peripheral cables to the appropriate connectors on the
   back of the computer. Reconnect the power cord.

NOTICE TO 3000/4000 USERS: Be sure to save your new hardware configuration
into memory. Use the Setup program on the Utilities diskette that came with
your computer. (For more information, see your Installation and Operation
Manual.)


(SMM/jlc-03/23/94)