Basic HTML Version
DEDICATED
GROUNDED
SWITCHES
~
r:r"
0-
Green
7
Green-
Green-
Green-
Green-
FLIPPER
Black
Blue
ViDlet
Gray
GROUNDED
J206-5
J206-6
J206-7
J206-9
SWITCHES
U20-14
U20-13
U20-12
U20-11
BLACK-GREEN
LEFT
LEFT
K-I-C-K J208-13
SPINNER
CART
ADVANCe
PATH
S1
61
RIGHT
SPINNER
72
RIGHT
RAMP
MAKE
SWITCH MATRIX
68
78
SWITCH MATRIX CIRCUIT
r--------------------------------------
,
: Column (example)+12V
:
""""""""'-'-I-'-'-+-"'-+--
I
lK
I
D
ULN2803
=t.
J206
I
----1[>=--B __
__,__~AO 1
0
LJ :
Green-XX
t'"!'-~i
470pf
74HC237
:
I
+5V
CPU BOARD : PLAYFIELD
ROW
SWITCH OPEN H
SWITCH CLOSED L
The microprocessor is constantly strobing the column side of the switch. When point "A" on the column
circuit toggles low, the column side is active. When a switch closes, the row side of the circuit activates.
The
"+"
input to the LM339 drops below +5V, therefore, its output is
low,
Corresponding row and column
switches must be low at the same time for the switch to be considered closed by the microprocessor.
When the switch opens, the "+" input to the LM339 is above +5V, its output is high and the row is inactive.
3-2