I still like the idea of using the LSI Logic family instead of the
IDT. For a project like this they have some advantages - mostly that
the DRAM and bus sizing stuff is on-board. They have three models
that I have info on - 33000 which is a MIPS 3000 core plus their
interface logic, 33020 which has the same mips core + glue logic +
plus a bit-blit engine and RAMDAC interface (for xterms on a chip),
and finally the 33050 which is a 33000 with MIPS FPU. I believe they
all have a 4k/1k i/d cache and come in PGA packaging. (No lousy 84PLCC
sockets!)
As for I/O busses - the ISA bus IS a simple 8-bit bus. I don't see
what all the whining is about. VESA is kinda nasty and not well
defined. If we are going to invest in a high speed bus, make it a
processor local bus, where some speed can be used not wasted
generating a bunch of other control signals.
As for FPGAs, I believe AMD gives away their PALASM s/w to program
MACH devices, I also have s/w for the Intel IFX780 and Xilinx which is
NOT free at work. For a project like this FPGAs might have some
advantages - reconfiguration, one physical part to perform several
different tasks, real estate reduction, speed, and perhaps cost if the
s/w is not too expensive.
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