On 09.11.2015 20:15, Eric Smith wrote:
On Mon, Nov 9, 2015 at 7:04 AM, Brad Parker <brad
at heeltoe.com> wrote:
I was wondering about software. Is anyone
planning to turn those schematics
into verilog?
I'm working on dumping the microcode.
Your post overlapped with mine...
The WD9000 board contains one WD chip for which no
documentation is
available, the WD2083U-04.
It is indeed an interrupt priority encoder.
I believe it is identical to the am25ls2513, as that is what is used in and early version
of the schematics.
Jos
When I traced the signals it appeared to be
a custom interrupt and DMA request prioritizer. That
appears to be
confirmed by the recently found WD9000 schematics (also on Bitsavers).
I suspect that the WD2083 is a mask-programmed PLA.
Other than the WD90 chipset and the WD2083, all of the chips on the
WD900 board were readily commercially available and reasonably well
documented.