yonder@netcom.COM (Christopher Russell) (06/14/91)
Could somebody give me some tips on setting up the
centronics port for I/O.
I have tried (in Sozobon):
Giaccess(data,15+0x80) ;0x80 = bit 7 = write
Then to test to see if this works I try to STROBE using On/Off/Ongibit(5),
in hopes that CHR$(data) will print out on my printer. Doesn't work.
Also when I try reads:
data = Giaccess(0,15)
with nothing connected to the printer port, I get 0 returned. I think I
should get back $FF, what do you think?
Anyways, I just started playing around, but I would like to use the
parrallel port to read and write data (I'm playing around with a
PowerGlove).
I've also tried to use assembly:
lea $ffff8800,a0 ; ff8800 = GI chip address
move.b #7,(a0) ; I want to let the GI chip know I want reg. 7
But the move gives me a bus error. I tried do a Super call first, but
I still get the bus error.
I'll admit that this is the first stuff I've written on my Atari
using these calls. I've got a couple of the Abacus books that I'm
using for reference.
Optimum would be if someone could show me a couple of short examples
for both read and write to the port.
Thanks.................
--
Christopher L. Russell (yonderboy) Phone: (408)378-9078 Campbell,CA
yonder@netcom.COM or clr40@amail.amdahl.com or chrisr@leland.stanford.edu