[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

Re: where can i download the various OS's for my GS?

 To: Michael J. Mahon
Michael J. Mahon wrote:

aiiadict@gmail.com wrote:

On Apr 23, 8:52 pm, "Michael J. Mahon" <mjma...@aol.com> wrote:


Yes, but I'd like it as an extension of BASIC.SYSTEM, since
my fingers have already memorized its commands, and my
Applesoft programs depend on it.  ;-)

I'm guessing that such an extension could fit in just one
page of high memory...



So catch command line input with your command processor,
if it doesn't match any of YOUR available commands, run
it through the basic.system processor (basic.system will
RTS back to your pre-processor, which then RTS back to
prodos command line blinker...

if it is a match to one of YOUR commands:

1)check if it is already resident in RAM.  If it is, execute it
2)if not in RAM, load from disk, keep a flag that says
YOURcommand#x is loaded,  and execute...

that would be nice...  if you weren't using 5.25 disks,
you could put the command processor + loaded commands
into the disk II driver space at $d000


It would also be good to automatically *unload* a command
if there is a demand for RAM.

Since there's no good hook for determining when, say, an
Applesoft program wants to use high memory, it's probably
best to write the handler to deal with all commands as
"overlays" with no continuing claim on RAM.
Or, a small kernel which can adjust himem: and load the utility, which must be relocatable, wherever. This could actually work fairly quickly if the 'modules' were in /ram or a very fast disk. 

Cheers,
Mike T.
--- Synchronet 3.14a-Win32 NewsLink 1.85
A2Central.com - Your total source for Apple II computing.