[Coco] Graphics on NitrOS9 Level 1 v3.3.0 (CoCo 1)

[Rogelio Perea]

Am having a bit of a problem running any GFX functions on my CoCo 1 (64k F
board) with the latest v3.3.0 NitrOS9 Level 1 (6809). Have been
experimenting with this for a while and tried and re-tried to make sure I
wasn't missing out any steps.

Thing is that no matter what I try to do something as simple as drawing a
circle on the 256x192 screen, NitrOS9L1 bombs out - say this procedure:

dim delay:integer
run gfx("mode",0,1)
run gfx("clear")
run gfx("circle", 128,96,20)
for delay=1 to 1000
next delay
end

aborts with a Module Not Found error (#221). GFX is in the CMDS folder and
does get loaded into memory first call to GFX in the Basic09 program, I
have tried loading it before launching Basic09 to no avail.

I keep my stock (more or less) OS9 Level 1 v2.0 close and with that system
I have no issues at all running graphics in this hardware setup, outside of
some careful memory considerations everything works.

Now, OS9L1v2 relies on a module called GRFO which was introduced with this
release, without it the advanced graphics functions will not work. GRFO has
to be loaded prior to launching Basic09 or running any procedure that
requires it, unlike GFX it won't automatically load - can be set in the
boot so no loading is required, then it just sits there doing nothing until
graphics are used...

Prior to v2, the earlier OS9Level1 releases appeared to handle all graphics
through CCIO but don't quote me on that, probably I read about this
somewhere. GRFO was absent in those releases.

NitrOS9L1v3.3 has a GRFDRV in the CMDS module, this is reminiscent to me of
OS9L2. Is this Level 1 GRFDRV supposed to do the work of GRFO? There is
little if anything available on graphics for OS9 Level 1 (and NitrOS9 L1)
so I am at the end of the rope on my curiosity led trip.

I have tried loading a copy of GRFO into NitrOS9L1 and it does not work,
keep getting the same Module Not Found error. Now, if I load GRFDV at least
I get a blank hi-res screen but the computer hangs only to regain control
of it with a reboot.

Help a lo-res graphics OS9/NitrOS9 nut here :-)

-- RP