[comp.sys.ibm.pc.hardware] ?covax voice master 2 programming

ray@ariel.ucs.unimelb.edu.au (Douglas Ray) (05/11/91)

I've just got one of these (8 bit da/ad) cards:  has anyone already
worked out how to run one from the i/o ports (as opposed to using the
supplied software)?   Or has anyone disassembled the library routines
rec8 and say8?   I'd rather avoid disassembling the binary.

Also, the encoding format: 2's complement?
					- douglas
					doug@unimelb.EDU.AU

ray@ariel.ucs.unimelb.edu.au (Douglas Ray) (05/13/91)

From article <652@ariel.ucs.unimelb.edu.au>, by doug@unimelb.edu.au (Douglas Ray):
> I've just got one of these (8 bit da/ad) cards:  has anyone already
> worked out how to run one from the i/o ports (as opposed to using the

turns out this is easy.  Just read from or write to the port;  there's no
interrupts to tell you when data's ready or such, it just goes as fast as
it can.   Card uses all standard chips: NS ADC0804, and so forth.

encoding is 8 bit:	FF h	    -> +1
			80 h(or 7F) ->  0
			00 h	    -> -1
and I think linear but not certain.
 					- douglas
 					doug@unimelb.EDU.AU