Re: What exactly WAS Apple Pascal?

[mjmahon@aol.com (Michael J. Mahon)]

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!  ;-)

-michael

Check out parallel computing for 8-bit Apples on my
Home page:  http://members.aol.com/MJMahon/