I/O Channel Description
A9-AO:
Address lines 9 through 0 are used to
address the Game Control Adapter.
D7-DO:
Data
lines 7 through 0 are the data bus.
1""""'\
lOR, lOW:
I/O
Read and
I/O
Write are used when read-
ing from or writing to an adapter (IN, OUT).
AEN:
When active, the adapter must be inactive
and the data bus driver inactive.
+SV:
Power for the Game Control Adapter.
GND:
Common ground.
AI9-AlO:
Unused
MEMR,MEMW:
Unused
DACKO-DACK3:
Unused
IRQ7-IRQ2
Unused
DRQ3-DRQ1:
Unused
ALE,
TIC:
Unused
I""""'\C
LK, OSC:
Unused
1/0
CHCK:
Unused
I/O
CH
RDY:
Unused
HRQI/O
CH:
Unused
RESETDRV:
Unused
-Sv, + 12v, -12v:
Unused
Interface Description
The Game Control Adapter has 8 input lines, 4
of
which are digital
inputs and 4
of
which are resistive inputs. The inputs are read with one
IN
from address x'20 1'.
The 4 digital inputs each have a
lK
ohm pullup resistor to +SV. With
~
no drive on these inputs,
a'
l'
is
read.
For
a
'0'
reading, the inputs must
be pulled to ground.
The 4 resistive inputs, measured to +SV, will be converted to a digital
pulse with a duration proportional to the resistive load, acccording to
the following equation:
Time
= 24.2
fJ-sec
+ 0.011 (r)
fJ-sec
2-119