[net.micro.atari] ST internals

bds@mtgzz.UUCP (b.d.szablak) (10/18/85)

Question for ST developers:

Does the ST allow you to set the interrupt vectors, and can the ST
generate timed or periodic interrupts?

Any other comments about ST internals would be welcomed as well.

															  Bruce Szablak
															  ihnp4!mtgzz!bds

djb@riccb.UUCP (Dave J. Burris ) (10/21/85)

> Does the ST allow you to set the interrupt vectors, and can the ST
> generate timed or periodic interrupts?
> 

Yes and yes. There is one programmable timer reserved for applications
programs. There is a BIOS routine that allows you to redefine vectors.

-- 
Dave Burris
..!ihnp4!ihopa!riccb!djb
Rockwell Switching Systems, Downers Grove, Il.

Felton.PA@XEROX.ARPA (10/21/85)

I don't have the technical information to answer the question of
interrupt vectors  with specifics. But, I do know that the ST can change
the color registers scan line by scan line just as the Amiga and old
Atari 800 could. This is usually done with "periodic interrupts".

I am trying to program the ST in Hippo C with grossly inadequate
documentation about the machine. Can anyone tell me how to read the
joystick ports. Also, if any one knows, how do you use the BitBlt
capabilities.


John

davecl@shark.UUCP (Dave Clemans) (10/24/85)

You can definitely play tricks to get large numbers of colors visible
simultaneously.  Neochrome 0.5 (a very good color paint program available
free from Atari to any ST purchaser) shows around 200 colors at once
in its color selection area.

dgc