TI-H: ti92 link port
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TI-H: ti92 link port
hi,
i am working on an io expander for my ti92, i 've found lots of things
for hardware but the hardest part is still the software. How can i set
io wires.
i wanna do manal input/output (i set this wire to +5V and this one to 0V
i wait 10ms and ....).
i 've found this in fargo doc :
---------------------------------------------
:RW [60000E]
<.......0|........> = set red output, if direct port access enabled
<......1.|........> = set white output, if direct port access
enabled
<.....2..|........> = read red output
<....3...|........> = read white output
<.6......|........> = enable direct port access
<........|76543210> = read a byte from the receive buffer (1 byte
buffer)
<........|76543210> = write a byte to the transmit buffer (1 byte
buffer)
---------------------------------------------
this in sound drivers :
------------------------------------------------
sound:
move.w #$2700,sr ;disable interrupts for
;smoother sound
move.b #00,($60000e) ;turn off red & white
wires
or.w #$0c00,($60000e) ;turn them on
move.l d6,-(a7) ;save freq
-------------------------------------------------
i don't really understand how this work, if someone could explain to me
that would be nice ...
i have done this :
----------------------------------------
move.w #%0000000000000000,($60000e) ;turn off
red & white wires
WriteStr
#5,#30,#4,step1 ; show "red and
white wire to ground"
jsr userlib::idle_loop
move.w #%0000001100000000,($60000e) ;turn off
red & white wires
WriteStr
#5,#60,#4,step2 ; show "red and
white wires to +5v"
jsr userlib::idle_loop
jsr doorsos::reset_link
rts
;exits the program
-----------------------------------------
this crash my calc and i don't even get the second message ...
i am working on a ti92+ but want to make a program which'll work on all
ti92 so any informations, explainations .... is really welcome.
thanx
thomas
sarfata@altern.org