Atari Asteroids Deluxe Signature Analysis Guide

ASTEROIDS  DELUXESIGNATURE  ANALYSISGUIDE 

1IntroductionThis guide is intended as an aid to troubleshooting the Asteroids Deluxe video game PCB.
The Signature Analyzer used to produce this guide was an HP5004a.  If it is found that the
signatures hold up for other makes/models of Signature Analyzers then please let me know
and I can add some kind of compatibility list to the document.  Suggestions of any kind to
improve this document are always welcome.
To get the most out of the guide you’ll need
Signature Analyzer (HP5004a)
Schematics for...

2The probe column refers to either the Start, Stop or Clock probes from the Signature
Analyzer.
The trigger column sets up the Start/Stop/Clock buttons on the front of the Analyzer.  I have
used –ve to indicate the negative going edge of the pulse (or the falling edge).
I have used +ve to indicate the positive going edge of the pulse (or the rising edge).
The IC Pin column refers to the point where the appropriate probe should be attached.
The Test Pt. column refers to an equivalent Test Point on the...

4What To Do When You Find An Incorrect SignatureIf you find a signature that doesn’t match the guide, check your set up first.  If your set up is
OK then you’ll need to trace the fault.  Rather than having a long winded ramble from me it
would be better to look at the following link on Al Kossow’s page.  If you haven’t already
had a look at his site then I’d definitely recommend having a look as it’s a bit of a gold mine.
http://www.spies.com/arcade/TE/SigAnalNotes.pdf
After you’ve had a look through the...

**  Tie the Watchdog Disable test point toground  **1.   Address Lines
A.  SA Settings for Address Buffer Test
Probe    TriggerIC Pin    Test Pt.
Start-veC2-25
Stop-veC2-25
Clock-veC2-39     f2
B.  Signatures
Logic ProbeSignalSignature
On IC/PinName
C1-20+5V0003
C1-9AB0UUUU
C1-12AB1FFFF
C1-7AB28484
C1-14AB3P763
C1-5AB41U5P
C1-16AB50356
C1-3AB6U759
C1-18AB76F9A
B1-18AB87791
B1-14AB96321
B1-9AB1037C5
B1-5AB116U28
B1-7AB124FCA
C2-23A134868
C2-24A149UP1
C2-25A1500012.   Address Decoding
A.  SA Settings for...

2D5-40066 (*)
E4-87U7C
L5-1DMAGO383U
L5-2EAADDRLP759
L5-3WDCLR90P8
L5-4EXPLODEUA0P
L5-5A43F
L5-6EACONTROLU5FA
L5-7AUDIO81F6
L5-9NOISERESET1A35
B8-1300UP
B8-12A43F
B8-11DMARESETA43F
**  Remove jumper from R/W test point  **
3..Watchdog Circuit
A.  SA Settings for Watchdog Circuit Test
Probe    TriggerIC Pin    Test Pt.
Start-veC2-25
Stop-veC2-25
Clock-veC2-39     f2
**  Tie L5-12 to ground  **
B.  Signatures
Logic ProbeSignalSignature
On IC/PinName
C5-14+5V0003
C5-6752C
D4-60398
D4-80000
**  Remove jumper...

3C.  SA Settings for ROM1 Test (E/F1)
Probe    TriggerIC Pin    Test Pt.
Start-veL2-5
Stop+veL2-5
Clock-veC2-39    f2
D.  Signatures
Logic ProbeSignalSignature
On IC/PinName
E/F1-9DB0UOF3
E/F1-10DB10UCU
E/F1-11DB20CA5
E/F1-13DB3A391
E/F1-14DB47F79
E/F1-15DB5U77P
E/F1-16DB6H494
E/F1-17DB7052H
E.  SA Settings for ROM2 Test (F/H1)
Probe    TriggerIC Pin    Test Pt.
Start-veL2-6
Stop+veL2-6
Clock-veC2-39    f2
F.  Signatures
Logic ProbeSignalSignature
On IC/PinName
F/H1-9DB0P65C
F/H1-10DB16FH0...

4**  The numbers in brackets are the pin assignments
when an AM8304B is used as opposed to a 74LS245
**
7.   Vector Generator Address
      Selector
A.  SA Settings for VG Address Sel Test
Probe    TriggerIC Pin    Test Pt.
Start-veC2-25
Stop-veC2-25
Clock-veC2-39    f2
**  Tie K2-1 to ground  **
B  Signatures
Logic ProbeSignalSignature
On IC/PinName
K2-1+5V0003
K2-4AM116U28
K2-12AM124FCA
L2-10VROM2F501
L2-11VROM1P693
L2-12VRAMAA2A
F2-9AM0UUUU
F2-7AM1FFFF
F2-4AM28484
F2-12AM3P763
H2-12AM41U5P...

5R2-16DDMA6725P
R2-17DDMA72604
C.  SA Settings for ROM2  Test (N/P2)
Probe    TriggerIC Pin    Test Pt.
Start-veL2-10
Stop+veL2-10
Clock-veC2-39    f2
**  Tie K2-1 to ground  **
D  Signatures
Logic ProbeSignalSignature
On IC/PinName
N/P2-9DDMA06334
N/P2-10DDMA12AH5
N/P2-11DDMA23431
N/P2-13DDMA3F67C
N/P2-14DDMA45H7C
N/P2-15DDMA57FFH
N/P2-16DDMA688U2
N/P2-17DDMA7A43310.   Vector Generator Data Buffer
A.  SA Settings for VG Data Buffer test
Probe    TriggerIC Pin    Test Pt.
Start-veL2-10
Stop+veL2-10...