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Re: ProDOS Plus

mdj wrote:

It is an interesting idea considering how much of the OS is actually
used in any given application. I would love to hear more of your ideas
in this regard.


It's most certainly practical. Indeed, Apple Pascal is an
implementation of such an idea, albeit without the optimisation phase.


Well, I meant in regards to just the P8 kernel.


There's an established protocol for Auxiliary memory usage. Some
limited testing that I did recently revealed that there really aren't
any "128k" Applications that don't use some of the aux language card.

The established protocol is this: If at application initialisation
time /RAM is connected, you are free to use the whole Aux memory area,
sans a small block in Aux. Language card bank 2 which is used by third
party drivers. Fortunately, I found that applications tend to respect
this barrier, so there's a whole 4K of useable RAM there.
What about the 2c which uses some low areas in the auxiliary 64k bank? I understood that this part of ram is also reserved.
As a mention, I think the Apex 128k developer might fail your tests. IIRC, it uses some aux ram while /ram is still connected. Granted, I never had any problems with the system and I think the /ram blocks are marked but I could never get Don (at microgram) to use the Apple method. 


If /RAM is disconnected, you are theoretically not allowed to use the
Language card at all. Anecdotal testing reveals most of the
'interesting' applications will either refuse to start, ask for
permission to start, or ignore this recommendation.
Does this imply that the 16k language card affects the 16k memory area in aux64? 


It really *is* a no-go zone. At a minimum, depending on this area will
make it impossible to run AppleWorks or Merlin 8. Since these are holy
applications to either the Apple II user community, developer
community or both, it's a non-starter.

I really feel it's a non sequitur to imagine a "turbo ProDOS 8" that
really only power users are going to be interested in, and then set
the hardware requirements to that of a stock Apple II. I would think
that anyone interested in this project is going to have a RamWorks or
similar card, or at the least, be prepared to source one in order to
be involved.
Initially, I was thinking along the same lines. During discussions with Michael Mahon, his ideas offer other possibilities. I suppose in the end it would really be up to the person or persons who develop such a system. 


ProDOS 8 does a pretty good job of exploiting the 128k Apple II
platform, and there's little functionality you can practically add to
it within those constraints, with the exception of a couple of small
behavioral mods to remove some limitations.
So your suggesting something which will take advantage of multiple memory banks? I don't have much experience with 'Slinky' ram cards so I don't know specifically how those work but I think the more banks you use, the more complex the system becomes. You quickly lose compatibility with existing programs. You could still maintain file compatibility though. 

Cheers,
Mike T