CompuPro - Disk 1
The Disk 1A was as CompuPro's first
floppy disk controller. It still used an Intel 8272 or NEC 765A floppy disk
controller instead of a at the time, then more common Western Digital 1791-7
chips. The board had a basic serial I/O port to boot the system for the first
time. with CompuPro's disk software.
What was interesting about both the
Disk1 (and Disk 1A) was that the boot ROM had code which via a switch
selection could be used to work with either a 8085/Z80, a 8088/8086/80286, a
68000 or a 32016 CPU based system. The board handled data transfers via 24 bit
DMA with the ability to cross 64K boundaries. There was a priority
arbitration scheme for the on-board DMA circuitry that will allow up to 16
temporary bus masters to operate without conflict. There was an advanced
digital data separator for reliable data transfers. No cap or resistor
adjustments were required. The board had provisions for running both 5.25" and
8" floppy drives though not at the same time. %' drives required a slight board
modification and careful cable connector seating.
Every effort was taken to make it easy
for the first time user to get a floppy disk system going in their system.
The manual gave detail descriptions of hardware and software combinations
needed. The default board port addresses were C0H - C4H. Apparently 5" drives
are different (CCH to CFH).
The serial port on the DISK 1 was
designed for initial system startup only and should not be used as the console
device for longer than required to patch the BIOS. Since this port is controlled
entirely by software, its baud rate was dependent on the host processor's clock
rate. See the manual for details.
The manual can be obtained
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