Re: What exactly WAS Apple Pascal?

[exegete@nunya.biz]

Paul Schlyter wrote:
> In article <40f7d453$1_5@corp.newsgroups.com>,  <exegete@nunya.biz> wrote:
>
> > Paul Schlyter wrote:
> >
> >
> > > UCSD Pascal was a 16-bit environment with all the limitations that
> > > comes with such an environment such as max 64K address space.  Even
> > > the Z-machine (the interpreter used for Zork and other Infocom games)
> > > had expanded a bit on that and used a 24-bit address space.
> >
> > The last version (1.3) utilized the 128K of the //c and IIe.
>
>
> Perhaps by putting the P-machine in parts of it and using the rest
> for disk buffers?  However, the UCSD system used a 16-bit program
> counter, which means the P-code coldn't occupy more than 64K.

The 64K system allows 32 segments, the 128K system 64 segments (whatever 
that means) In addition, 64K allows one library on line per program, 
128K allows up to six libraries on line per program. The Editor has a 
file capacity of 17920 characters in the 64K system, 32256 with the 128K 
system. In the 64K system about 38K is available for P-code, 6502 code, 
and data. They all share the same memory space. In the 128K system, 
about 43K is available for 6502 code and data. An additional 38K or so 
is available for P-code

The above are quotes from the Apple II Pascal 1.3 Workbench.

Roy

> CP/M+ did something similar: it used bank switching to store the
> BDOS and BIOS in a different memory bank, making a larger part of
> the main 64K memory bank available for applications.  Although the
> applications here executed 8080 machine code rather than P-code.
> On the Apple II, the "CP/M Card" had its owh 64K and also used the
> Apple's 48K or 64K RAM as the extra memory bank.
>
>
> > It also supported 3.5" disk drives. That 800K of storage was a big
> > improvement over 1-4 140K drives.
>
>
> I can easily imagine....
>
> A friend of mine patched Apple Pascal 1.1 to run on 80-track double
> sided 5.25" floppies, which yielded not 800K but 640K -- but that too
> was a huge improvement over the 140K standard Apple II diskettes.
> I did the same to Apple DOS 3.3 and Apple CP/M (both Softcard CP/M
> and Appli-Card CP/M).  And here Apple Pascal and Apple CP/M showed one
> big advantage over Apple DOS: one disk volume could be 640K large.
> In Apple DOS one disk volume could not be larger than 400K....



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