36bit still in use ?

[Lars Brinkhoff]

Rich Alderson <RichA at LivingComputerMuseum.org> writes:
> From: Eric Smith
>>> It was?  During my stint at XKL, I was told the Toad-1 I was
>>> working with was an FPGA implementation.  Maybe it was an
>>> experiment, but it seemed to work pretty well.  But then, I was a
>>> telecommuter, so maybe some information was jumbled in
>>> long-distance transmission.
>
>> You guys probably have more information about this than I do, but
>> my understanding was that the Toad-1 CPU required multiple FPGAs,
>> CPLDs, and other logic, while the Toad-2 CPU is a single FPGA.
>
> Lars, Eric is correct.  The Toad-1 is a multi-board computer system
> (at minimum, the XKL-1 CPU, one XMG-1 memory, one XNI-1 Ethernet
> interface, and one XRH-1 SCSI interface, in a 7-slot backplane).
> Each board used several programmable parts, from Altera and Xilinx.
> In particular, the CPU was a pair of Xilinx parts for the microcode
> engine, with an AMD 2900 family sequencer (I forget the particular
> part number).
>
> The Toad-2 (and the 1U rack mount unit is *not* a Toad-2, but it
> does contain two of them, thus the label) is a single FPGA
> implementation of the Toad-1 (mutatis mutandis: no SCSI, but it
> talks to SD cards, for example).

Ah, that explains it.  Thanks!