Williams D8224 Sound Board EPROM and CPU Type Jumpering Guide



EPROM Jumpering Information

D8224 Sound Board EPROM Jumpers
View a high resolution image of the D8224 sound board jumpering information

The D8224 sound board is common to many Williams video games and pinball machines. This page is primarily aimed at the video games but also applies to the Pinball machines.

Different games require this board to be jumpered differently according to the size of the game ROM being used (ie a 2716, 2516 or 2532 EPROM) and if the game requires the optional speech board (Sinistar and pinballs).

The image to the left shows the board and the jumpers required have been highlighted in various colours to help you identify in conjunction with the table below the jumpers required for your game. Any other jumpers that may be fitted are not required for games listed and should not be fitted.

BLUE jumpers are required for all games
YELLOW jumpers are required for games using 2516/2716 EPROMs
GREEN jumpers are required for games using 2532 EPROMs
The RED jumper is required for all games NOT using Speech

Click on the boards image or HERE for a high resolution image.



Game Names EPROM Name EPROM Type Jumpers Used Board Mode
Defender
Stargate
Video Sound ROM 1
Video Sound ROM 2
2516
2716
W 1 W 2 W 5 W 7
W 9 W 10 W 15
Sound Only
Robotron
Joust
Bubbles
Blaster
Sinistar (Cockpit rear)
Video Sound ROM 3
Video Sound ROM 4
Video Sound ROM ?
Video Sound ROM ?
Video Sound ROM 10
2532
W 1 W 3 W 4 W 5
W 7 W 10 W 15
Sound Only
Sinistar (Upright)
Sinistar (Cockpit front)
Video Sound ROM 9 2532
W 3 W 4 W 5
W 7 W 10 W 15
Sound and Speech



6808/6802 CPU On-board RAM Jumpering Information

D8224 Sound Board CPU Jumper
View a high resolution image of the D8224 sound board jumpering information

The D8224 sound board uses the Motorola 6808 CPU chip. Since the Motorola 6802 CPU chip is 100% compatible it can also be used as a drop in replacement.

So, what's the difference between a 6808 and a 6802? The 6802 has on-board RAM in addition to the functions provided by the 6808 though it is not enabled by default.

This can be very handy when repairing these boards if the 6810 RAM chip has failed. Some, but not all 6810 failures can be repaired by fitting a 6802 and enabling the on-chip RAM. If the faulty 6810 is affecting the buses then you will also have to remove the 6810 from the board. I test the 6810 RAMs in circuit using a Fluke 9010A troubleshooter with a 6808/6802 POD.

Fortunately Williams thought of this when designing the Sound boards and so by removing jumper W14 the 6802's on-board will be enabled (this pulls the RAM Enable signal, pin 36 of the 6802 to a high state). Unlike the other jumpers on the sound board it is not the zero ohm resistor type, rather a track on the board. The photo opposite shows the jumpers position under R30 (which is close to the Crystal), simply cut this track to enable the 6802's on-board RAM. To disable the RAM, for instance if you want to fit a 6808 again, then remove R30 and fit a zero ohm resistor grounding pin 36 of the 6802/8.

Click on the boards image or HERE for a high resolution image.


Disclaimer: Although I have done my best to ensure that all information contained on this
page is correct, I can take no responsibility for damage to your game, its boards or yourself!