Basic HTML Version
,--------------------~~~-~~~~~~--------~
: CPU BOARD
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:
+12V
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L
_
Coin Acceptor Switches
01 - Left Coin Chute
02 - Center Coin Chute
03 - Right Coin Chute
04 - Fourth Coin Chute
Dedicated Input
DEDICATED SWITCHES
-----------------,
COIN DOOR :
INTERFACE
:
BOARD
:
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4
--+--0
(U16-5)
D8
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Control Switches
05 - Normal Function, Service Credits; Test Function, Escape
06 - Normal Function, Volume Down; Test Function, Down
D7 - Normal Function, Volume Up; Test Function, Up
08 - Normal Function, Begin Test; Test Function, Enter
DEDICATED SWITCH CIRCUIT
SWITCH
OFF
ON
OPEN
CLOSED
J20S;
r------------
COIN DOOR
INTERFACE
BOARD
Switch
Acceptor
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Black
,-~~~10r+--------~lSr-------~
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_j
The dedicated switches operate similar in the matrix, except that instead of a column circuit there is a direct
tie to ground, Therefore, the column side is constantly active (low).
When a switch closes, the row side (dedicated input) of the circuit activates, The "+" input to the LM339
drops below +5V, therefore the output is low. Since the row circuit (dedicated input) is tied directly to ground through
the switch, the switch is considered closed by the microprocessor.
When the switch opens, the
"+"
input to the
LM339 is above +5V, it output is high and the row is inactive
3-3