Re: What exactly WAS Apple Pascal?

[Don Bruder <dakidd@sonic.net>]

In article <cd955v$2l6$1@freenet9.carleton.ca>,
 et472@FreeNet.Carleton.CA (Michael Black) wrote:

> Michael J. Mahon (mjmahon@aol.com) writes:
> > Zorin the Lynx wrote:
> > 
> >>Thanks for the great answers.. I used them to do a bit more research to 
> >>learn about the fascinating world of Apple Pascal. The fact that it's 
> >>interpreted explains why SmartCom I was on the slow side!
> >>
> >>It's amazing how much they packed into the tiny memory capacity of the 
> >>Apple II back then. A Pascal compiler? Whoah. I have a hard time 
> >>imagining it these days with gigs of disk and memory available for us to 
> >>waste...
> > 
> > The "grand idea" behind the UCSD system was not portability
> > through P-code, since that was inherited directly from Wirth's P2
> > system, but _compactness_ that made it possible to host Pascal
> > on a 64KB microcomputer.
> > 
> > P-code and the P-code interpreter were the means to achieve the
> > needed memory efficiency, and the cost was somwhat slower speed.
> > 
> > A little later, Philippe Kahn saw other ways to achieve the required
> > compactness to fit a Pascal IDE into 64K, and he did it using
> > Z-80 machine code in Turbo Pascal.
> > 
> > BTW, putting the P-code interpreter into on-chip ROM, as the p-Engine
> > did, was hardly making a "hardware" implementation of a P-machine.
> > I'm reminded of a time in the early-1980s when some wonk at TI said
> > that now that they could burn software into ROM, making it "hardware",
> > the industry would finally be freed from software bugs!  ;-)
> > 
> It's been a long time, but I thought there was a computer or two that
> directly interpreted p-code.  Instead of 6502 (or any CPU) op-codes, the CPU 
> would interpret p-code directly.  I thought there was at least one very
> fancy computer built in Europe that did this, and if I'm remembering, it
> used common logic to build it up.  But I also thought there was a bit-sliced
> computer that interperted p-code directly too.
> 
>    Michael
> 

I'm absolutely certain that there was a CPU that used P-code as its 
native machine language. I'm also absolutely certain that it was 
marketed as a (quite pricey, comparatively speaking) card to be plugged 
into the Apple II. I *THINK* the card was sold under the name 
"P-engine". What I'm not certain about is what the chip number was. For 
some reason, the 68000 is ringing a bell, but I'm pretty sure that's not 
right, 'cause that was the CPU for the original Mac/Lisa/Apple III, and 
NONE of those use P-code natively.

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