30 Nov
2000
30 Nov
'00
6:37 p.m.
From: Roger Ivie <rivie(a)teraglobal.com>
That's an extremely interesting remark because of
two of
the rumors I heard about the WD P-engine:
1) It failed because a Z80 could execute P-code faster
2) It was a remicrocoded 11/03
Z80 was a good pcode engine, in 1978 the fast ones were 4mhz
and the PDP-11/03 in the guise of an H11 was a bit faster.
The WD Pascal microengine was the WD13 chipset as
was the LSI-11 and the S100 box (forgot the name). The uEngine
was a failure as WD was not a reliable vendor back then and
it was buggy. It did run the pcode fastest of the pack then.
The PDP-11 and to a lesser extent z80 had the addressing modes
and instuction set needed to build a good stack oriented engine.
UCSD was not so much a failure as the leading edge. With the
avilability of natively compiled languages that were faster or better
a P-code compiler was a weakness. The idea of cross platform
code portability in the form of a compiled HLL was a big winner
that remains.
Allison