Atari Centipede - Page 61

Centipede
3. Checking
Address Decoder
A. CAT Box
Settings for Address Decoder Test
4.
Checking
ROM
and Data
Lines
Probe
Trigger IC-Pin Test Pt.
Start
[
C2-25
Stop
—
1
C2-25
Clock
1
C2-39
<t>2
B. Signatures
Logic Probe Signal
Signature
on IC-Pin
Name Should
Be
A. CAT
Box Settings for
ROMO Test (I.C.
D1)
Probe
Start
Stop
Clock
Trigger
IC-Pin
Test Pt.
D1-20 ROMO
D1-20
ROMO
C2-39 <J>2
To obtain stable signatures from ROMO,
it may
be necessary
to
install
a
1000
pf
capacitor
from K3-11
to
ground.
K3-10
3C97
B.
Signatures
J3-8
ROM 3C97
-200
ROMs:
-300
ROMs:
J2-9
ROM3
51
U7
Logic
Probe
Signal
Signature
Signature
J2-10
ROM2
2960
on IC-Pin
Name
Should
Be
Should
Be
J2-11
ROM1
5P33
D1-9
DB0
5AF2
8H07
J2-12
ROMO
1H32
D1-10
DB1
3276
7916
H3-11
A8H2
D1-11
DB2
48UH
7052
H3-10
C5P1
D1-13
DB3
P316
H3FH
H3-9 U550
D1-14
DB4
PF7A
H6F1
H3-7 9UC6
D1-15
DB5
H973
1322
H3-6 0UA5
D1-16
DB6
3F34
U577
H3-5
POKEY F733
D1-17
DB7
U638
FI
89
H3-4
4231
H3-3
SWRD
3580
C. CAT Box
Settings for ROM1
Test
(I.C. El)
H3-2
PF 4P5C
Probe Trigger
IC-Pin Test
Pt.
H3-1
RAMO A00H
Start
El -20
ROM1
J3-11
F6HP
Stop
1
El -20 ROM1
C5-8
F97A
Clock
1
C2-39 02
C4-6
EA
READ
0099
To obtain stable signatures from
ROM1,
it may
C4-5
EA CONTROL
U08U
be necessary to install a
1000
pf
capacitor
C4-4
EA ADDR
HF7A
from
K3-11
to
ground.
E3-3
INO 0294
K3-12
5554
D.
Signatures
-200
ROMs:
-300
ROMs:
E3-6
FnT 40A4
Logic Probe Signal Signature Signature
E3-8
PFRAMRD 4P5C
on
IC-Pin Name Should Be
Should Be
For the
following
four tests,
ground
J2,
pin
1:
El
-9
DB0
13PH
2956
J2-7
PFWR3
11U6
El-10 DB1
C4P5 18F6
J2-6
PFWR2 1C3F
El-11 DB2
11F3
F829
J2-5
PFWR1 4FH7
El-13 DB3
098
P
6200
J2-4
PFWRO 461
F
El-14 DB4 5H24
47C0
El-15 DB5
0548 F341
El-16 DB6
33P7
67FP
El-17 DB7 80AA 8UF5
2