Atari CX - Page 73

Softfire (Top Fire Button) Troubleshooting
F'
I Yes
Insert Diagnostic cart-
ridge into console.
Insert Game Controller
into Port
1.
manually select Pokey
Swapout and retest*
in
the following order:
With softfire button
IYes
1 held down9 are there I I
ad just test.
I
- No
Are there 5V p-p
I
I
Repair open trace
from
U13 Pin 3 to U7
Pin 16.
., A
f
Are there 5V p-p wave-
forms at
U13 Pins 9
& LO?
I) u7
2) U3
3)
U5
2
~ote:@
Port
1 check Pin 4, U13
Port 2 check Pin 2, U13
Port 3 check Pin 5, U13
Port 4 check Fin 1, U13
waveforms at U13
Pins 1,2,4 & 5?
sv wavefdrms at ~7
Pin 16?
CIWC* waveform at 1
yes -1
U13 Pin @ (see chart
Replace
U13.
below). Is it now low?
J
No
I
Check for opens from Repair
pin (see chart)
to port plug
and
game controller
If you are servicing a unit containing
PCB CA020108, chip designators have
been changed
from U to A.
I
Yes
CX 5200 Field Service fvlanual
Replace U 1 3
I
I
h
J
Are there 5'V p-p No
Yes
I
waveforms at U5
Replace U5
b
I J
I Depress & hold soft
I fire button. Is U13 I
Pin 3 pulsing?
Pins
12- & 13?-