[Coco] Re: Using Disk EDTASM

[Mark Marlette]

No idea. Never had a CoCo3 here in Germany when I was still coding...

Past tense???? So you are not coding anymore? :(

Best time to code for the coco, tools are awesome!


Quoting Torsten Dittel <Torsten at Dittel.info>:

> > 1) Setting the video mode on the Coco3 in assembly to the
> equivalent of
> > HSCREEN 2
>
> No idea. Never had a CoCo3 here in Germany when I was still coding...
>
> > 2) setting a single pixel on said screen aka HSET(x,y,c)
>
> Well, there are always two approaches: If you're lazy or don't have
> space or maybe don't need speed, you can make an (undocumented) call
> to
> the corresponding routine in the SDECB ROM of the CoCo3 (you have to
> know how to pass parameters, this might be complicated and slow and
> mightn't work with different BASIC versions). Otherwise, you have to
> programm routine on your own. It depends on the resolution of the
> screen, on the way its memory is addressed and on how many bits are
> actually present in a pixel. Things were quite easy in PMODE4 on the
> CoCo1/2 but on the CoCo3...
>
> > 3) reading from a joystick using asm
>
> There was a documented indexed jump to the BASIC routine (something
> like
> "JSR [$A00A]") but the routine was slow (because of a bug) at least
> on
> the CoCo1/2 (I used to use my own fast routine). "indexed jump"
> means,
> it jumps to a subroutine at the address which is stored in ROM
> location
> $A00A in this example (no jumping to $A00A!). The address which is
> stored there might change from ROM version to ROM version, but the
> place
> where it's stored ($A00A) never.
>
> Not much, but a point for someone else to jump in and correct me...
> Torsten
>
>
>
>
> --
> Coco mailing list
> Coco at maltedmedia.com
> http://five.pairlist.net/mailman/listinfo/coco
>