28 Cmos

If when powering the game up, it will not coin up because the battery is low. The following Procedure should be followed. Open the Back Door of the game, pull W1 out on the Video Board (Blue Jumper). Wait 2 minutes, power back on and insert W1 back in. Open the Coin Door and pull out bottom Interlock Switch. If the Language Select Frame does not come on the CRT, power down remove W1 again. Short pins 18 and 9 on U85, power back on and insert W1 back in. Leave the game on for 12 hours. If this Procedure does not work when you turn the game back on the battery may need to be replaced.

FIGURE 2-7 CURRENT LIMIT ADJUSTMENT

2.9 TEST POINTS

The following is a list of Test Points to be used when troubleshooting.

DATA/SOUND BOARD

DTP1

E

(Master Clock)

DTP2

Q

(Master Clock)

DTP3

LIC

Last Instruction Complete

DTP4

SÄ15

(Address Line)

DTP5

DA 15

(Address Line)

DTP6

Voice Clock

DTP7

SBSC

(Sound Processor Data Enable)

DTP8

DBSC

(Data Processor Data Enable)

DTP10

+5V

DTP11

Ground

TABLÉ 2-3 DATA/SOUND BOARD TEST POINTS

VIDEO BOARD

VTP1

Invert

VTP2

10MHZ

VTP3

VQ

(Clock Video Processor)

VTP4

VE

(Clock Video Processor)

VTP5

EXTAL

(External Clock)

VTP6

LIC

Last Instruction Complete

VTP7

VBSC

(Video Data Enable)

VTP8

VA 15

(Address Line)

TABLE 2-4 VIDEO BOARD TEST POINTS

TABLE 2-4 VIDEO BOARD TEST POINTS

If you ground any Data Enable Test Point (DTP7, DTP8, VTP7) the related processor will receive NO-OP and the address line will act like a 16 Bit Counter.

NOTES

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