[Coco] Re: Does NitrOS9 limit apps to =<64K?

[David J Bush]

--- Robert Gault <robert.gault at ...> wrote:
> Do some experimenting with Allocate RAM os9 F$AllRAM, Allocate High RAM 
> os9 F$AllHRAM, map specific block os9 F$MapBlk, clear specified block 
> os9 F$ClrBlk, and deallocate RAM blocks os9 F$DelRAM.
> ...
> You should be able to have about as much control of your Coco's memory 
> as you would from Disk Basic.

Fantastic, thanks for the info! I regret my CoCo isn't working now,
but I'm glad to hear apps can stake out whatever physical and logical
pages they want. I wonder, about how much RAM does NitrOS9 need for
itself?

This suggests that ML programs written for RSDOS might be portable to OS9
without making them entirely position-independent. Just "wrap them up" in
some PI code which will request the memory regions the app uses when
running under Disk Basic. Then the wrapper code will copy the app to the
new location. Switch to ROM mode if necessary, so the I/O Disk Basic
routines would be accessible. (This assumes your OS9 CoCo would still have
an RSDOS ROM in it somewhere.) Or, maybe the wrapper could contain the
RSDOS routines needed, which it would copy to the proper locations (which
it requested from OS9) in RAM mode. Then transfer control. Then when the
program exits, deallocate the memory as you said. Does this make any sense
at all?

Robert Emery <theother_bob at ...> writes:
> What an interesting statement, considering that Basic was always downplayed
> as being unable to access all that memory (of course I know better *now*)
> and OS-9 was "all that and a bag of chips".

Well, of course most Disk Basic users didn't know or care about assembler.