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SWTPC Minifloppy Disk Unit
Introduction
The SWTPC minifloppy disk unit is a dual drive, double sided, five-inch disk
unit. Double density operation is also available when using the DC-4 disk
controller board. The disk unit was designed specifically for the SWTPC 6809
computer. Although the disk unit was completely assembled and tested at the
factory, minor reprogramming of the circuit board may be necessary to operate with
your particular computer system. It is suggested that this instruction manual be
read completely before attempting to use the unit.
Jumper Programming the DC-4 Controller Board
There are five Jumper blocks on the DC-4 controller board that must be
properly programmed before the board is installed in the computer. Programming is
achieved by plugging the small plastic blocks onto the specified set of programming
pins.
( )
There are two Jumper locations near the bottom of the board marked 4/16. This
Jumper selects the number of address locations assigned to each I/0 port. If
your computer uses the earlier MP-B or MP-B2 motherboard, RESET switch on
RIGHT side of chassis, put the Jumpers in the 4 position. All other computer
installations should have the Jumpers in the 16 position.
( ) If you will be using the disk unit with a 6800 (not 6809) processor board or a
6809 using FLEX 2.5 or earlier, install the Jumper in the 00 position. All
other installations should have the Jumper in the 09 position.
( )
Unless specifically noted with a particular piece of software, both the IRQ
and FIRQ Jumpers should be in the NORM (OFF) positions or removed completely.
Interrupts are presently not used with this board.
Scanned and edited by Michael Holley Oct 23, 2000 [email protected]
Southwest Technical Products Corporation Document Circa 1978