DMA Hard Disk access

[Brian O'Connell]

It's me again.

Thanks for all your help guys. I've managed to access my hard disk via
PIO and also run a basic diagnostic about its specs, however, now I'm
going for the more advanced input/output with the hard disk: I want to
use direct memory access. First of all, does anyone know what the slave
dma is? I know there are seven dma channels, but which one(s) is the
slave. And is there anything I need to do to tell my hard disk what
channel I need to use or will it figure it out on it's own? Do I need
to issue commands to the dma like the hard disk, or do I just set it up?

You can download the code I have so far at
http://www.angelfire.com/pa2/ProgrammingRules/asm/dma.asm
but I must warn you, this code is rough and some stuff is simply
commented out. I also still have some dos calls in it for simple
print to screen things because I haven't added this code to my OS yet.
The sources I have been using for dma and ata can be downloaded from
http://www.angelfire.com/pa2/ProgrammingRules/asm/dma_rti.zip
http://www.angelfire.com/pa2/ProgrammingRules/asm/dma_vla.htm
http://www.angelfire.com/pa2/ProgrammingRules/asm/ATA.txt
also. NOTE: Last I knew, ProgrammingRules is CaSE SensItIVe.

Thanks to you all, that radios OS code has also come in handy on
various occasions.

Brian
________________________________________________________________________
Get Your Private, Free E-mail from MSN Hotmail at http://www.hotmail.com