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Cromemco XXU Board
Clearly one powerful S-100 board.
It contains a Motorola 68020 running at 16 MHz. The board came out in
1986. The S-100 bus had come a long way in 10 years!
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Cromemco's XXU processor board provided a bold leap in
microcomputer processing power, exceeding previously offered microcomputer speed
by a factor of three or more. By integrating a 16.7 MHz MC68020 microprocessor,
a 16.7 MHz MC68881 floating-point coprocessor and a 16 KByte two-set associative
data and instruction cache onto one S-1Q0/IEEE-69 6 card, the XXU offered
performance heretofore unavailable in a general purpose microcomputer at the
time. Using Cromemco's 2048KZ memory boards, which featured Cromemco's exclusive
double-word transfer extension to the S-100/IEEE-696 bus, data can be moved on
the bus at rates as fast as 8.33 megabytes per second. This was more than double
the transfer rate of previous Cromemco products.
The XXU also provided a real-time clock/calendar with
battery backup and a diagnostic/boot ROM. The clock had an accuracy adjustable
to within seconds per month. The combination of battery backup and high degree
of accuracy eliminated the tedium of entering time and date every time the
system was booted. The diagnostic/boot ROM made it possible to test the basic
system hardware prior to booting. This enabled configuration or hardware
problems to be detected and signaled to the user quickly.
The manual (no schematic) for this board can be obtained
here.
Other Cromemco S-100
Boards
ZPU
SBC 4KRAM
16K RAM
64KZ RAM
64KZ-II
RAM
256KRAM
8KBytesaver Bytesaver-II
16KPROM
32K Bytesaver
4FDC 16FDC 64FDC
WDI WDI-II
STDC
4PIO
8PIO TU-ART
D+7A I/O
Dazzler PRI
GPIB Board
XMU
XXU
Other Boards
This page was last modified
on
01/08/2011