RAM FAILURE is indicated by one to 10 beeps.
|Beeps||Suspect BAD ram chip|
Any bad ram must be replaced before game can check the other RAMs as well as to continue with self-test.
PROM FAILURE is indicated by two groups of numbers in upper left corner. If the screen displays "garbage" orthe logic produces strange audio or randomly activiates the coin counters, the chip at J1 (ROM3) is probably bad.
|Code||Suspect BAD rom chip|
If the EAROM is erased the number 4 FF will be displayed during the self-test. The 4 should disappear after a game is played.
2. Mini-Trak Ball test:
Roll the trackball controls in all directions. The centipede head should move around on the screen.
3. Switch Test:
One after another activate all switches including slam and coin. Each one should produce a beep.
4. Audio I/O Chip Test:
One after another, press and hold 2 of the control-panel switches and at least one of the coin switches. Volumn increases and pitch decreases with each additional switch that is activated.
5. Audio I/O Channel Test:
Press 1-player start button four time. You should hear a beep for each press of the button.
6. Background Color Test:
Press 1-player start button at least 16 times. Background color should change with each activation.
7. Color Object Test:
Press 2-player start button at least 16 times. Objects on playfield should change color.
8. Moving Object Test:
Watch the screen, and move the Track ball around. Place the moving object in an open area of the screen and press the fire button several times. Each press should change the moving object. At certain points the object will dissappear (this is not a failure).
9. Erasing the high score table:
Press ad hold the fire button and BOTH start buttons. 4 FF should then be displayed. The average game time data will also be erased, but is still displayed.