Re: ProDOS 2.0.3 Questions - from the Disk ][ Problem Guy

[dempson@swell.actrix.gen.nz (David Empson)]

In article <9310120602.AA18440@writer.yorku.ca>
wc8754@writer.yorku.ca (John Slonimsky) writes:
> If you remember my last article -- about five minutes ago by me -- I
> was about to check out ProDOS 2.0.3.  I had been using versin 1.8 up
> until now and I have  one question -->
> 
> "WHAT IS THE DIFFERENCE? I CAN'T SEE THE DIFFERENCE, CAN YOU SEE THE
> DIFFERENCE? 

Lots of differences.  For starters, version 1.9 replaces the standard
quit code ("enter pathname of next application") with a reasonable
file selector, provided you have an 80 column IIe or later.

This won't be an issue if you're already using a third-party file
selector such as Birds Better Bye.

Version 2.0 and later require a 65C02 microprocessor, because there
wouldn't have been enough space in the language card if it was limited
to using 6502 instructions.

The main changes I can think of:

- SmartPort interfaces with more than two devices per slot are
supported.  Additional devices are remapped into unused unit numbers.

For exaple, a SCSI card in any slot can now access up to 7 partitions
(assuming you have at least five unused unit numbers).

- ProDOS-8 can re-use volume control block entries, which allows more
than eight volumes to be online at once.

- Clock table updated for later years (only important if you have a
ThunderClock or compatible card).

- 2.0.3: the copyright message in the global page has moved up by one
byte, and a zero appears before it (after the device list).  This
avoids a problem with the standard routine to remove and replace the
/RAM volume if there are 14 devices online.

There are a few other minor changes, but I don't have the
documentation handy so I can't look them up.
 
> The only thing I can see is that it fixes a clock problem, but I don't have
> a clock.  Does this mean I can't tap any more power (or something) from my
> //e after going to all this trouble to get the new version -- was I hoping
> for too much?  What was I hoping for?

I don't know.  What were you expecting?

The language card is full - ProDOS-8 cannot have any major new
features added without replacing existing ones.  It could expand into
other memory areas (such as reserved areas of auxiliary memory) but
this would cause compatibility problems with many programs which break
the rules for using these areas.
-- 
David Empson                                                               
dempson@swell.actrix.gen.nz                                                
Snail mail: P.O. Box 27-103, Wellington, New Zealand