Bally 6803

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1 Introduction

Bally 6803 Board Set

The Bally 6803 game system, and the games themselves, were developed with extreme cost consciousness in mind. Bally used particle board cabinets with minimal artwork, cheaper materials and short cut techniques during these years of game development. Still, many of these games continue to be enjoyed by hobbyists now and will be for years to come.

2 Games

Game Title	Game Number	Sound	Displays	Keypad Used	Notes
Eight Ball Champ	0B38	Squawk & Talk	4 7-Digit / 1 6-Digit	Yes
Beat the Clock	0C70	Squawk & Talk	4 7-Digit / 1 6-Digit	Assumed Yes
Lady Luck	0E34	Cheap Squeak	4 7-Digit / 1 6-Digit	Assumed Yes
Motordome	0E14	T. C. S.	2 "Special" 14-Alphnumeric	Yes
Black Belt	0E52	T. C. S.	2 "Special" 14-Alphnumeric	Assumed Yes
Special Force	0E47	Sounds Deluxe	2 "Special" 14-Alphnumeric	Yes
Strange Science	0E35	T. C. S.	2 "Special" 14-Alphnumeric	Yes
City Slicker	0E79	T. C. S.	2 "Special" 14-Alphnumeric	Yes
Hardbody	0E94	T. C. S.	2 "Special" 14-Alphnumeric	Yes
Party Animal	0H01	Sounds Deluxe	2 "Special" 14-Alphnumeric	Assumed Yes
Heavy Metal Meltdown	0H03	Sounds Deluxe	2 "Special" 14-Alphnumeric	Yes
Dungeons & Dragons	0H06	Sounds Deluxe	2 "Special" 14-Alphnumeric	Yes
Escape from the Lost World	0H05	Sounds Deluxe	2 "Special" 14-Alphnumeric	No
Blackwater 100	0H07	Sounds Deluxe	2 "Special" 14-Alphnumeric	Assumed No
Truck Stop	2001	D-11581-2001	2 "Special" 14-Alphnumeric	No	Uses a sound interface board to process signals for sound board
Atlantis	2006	D-11581-2006	2 "Special" 14-Alphnumeric	No	Uses a sound interface board to process signals for sound board

Game model numbers provided by the Internet Pinball Database - http://www.ipdb.org

3 Technical Info

3.1 CPU Board

Bally 6803 CPU Board

3.1.1 CPU Board ROM Info and Jumper Settings

Game	U2	U3	Jumpers
Eight Ball Champ	Not Used	0B38-00803-0005	2, 4, 6, 8, 10
Beat the Clock*	Not Used	0C70-00803-0005	2, 4, 6, 9, 10
Lady Luck	Not Used	0E34-00803-0005	2, 4, 6, 8, 10
Motor Dome	E14A-42AAE-BX40	E14A-42AAE-CX4D	2, 4, 6, 8, 10
Black Belt	0E52-00803-0001	0E52-00803-0002	2, 4, 6, 8, 10
Special Force	0E47-00803-0004	0E47-00803-0005	2, 4, 6, 9, 10
Strange Science	0E35-00803-0001	0E35-00803-0002	2, 4, 6, 9, 10
City Slicker	0E79-00803-0002	0E79-00803-0003	2, 4, 6, 9, 10
Hard Body	E94A-12601-0000	E94A-12602-0000	2, 4, 6, 9, 10
Party Animal	H01A-12601-0000	H01A-12602-0000	2, 4, 6, 9, 10
Heavy Metal Meltdown	H03A-12601-0000	H03A-12602-0000	2, 4, 6, 9, 10
Dungeons & Dragons	H06A-12601-0000	H06A-12602-0000	2, 4, 6, 9, 10
Escape from the Lost World	H05A-12601-0000	H05A-12602-0000	2, 4, 6, 8, 10
Blackwater 100	H07A-12601-0000	H07A-12602-0000	2, 4, 6, 9, 10
Truck Stop	H08A-12601-0000	H08A-12602-0000	2, 4, 6, 9, 10
Atlantis	2006-12601-0000	2006-12602-0000	2, 4, 6, 9, 10

*Beat the Clock manual may state W8 in, W9 out. However, there was a service bulletin after the game was released stating the opposite.

3.3 Sound Boards

3.3.1 Squawk & Talk

Bally Squawk & Talk Sound Board

3.3.1.1 Cheap Squeak Sound Board

Bally Cheap Squeak Sound Board A080-91603-XXXX or Midway P/N M-051-00114-XXXX

The Cheap Squeak was designed as a lesser expensive sound board. It only utilizes a 6803 microprocessor, which allows it to function without 6821 PIAs and external RAM memory. This sound board is only capable of simple tones and sounds, but not speech. Although the Cheap Squeak is used in a handful of -35 based Bally games, Lady Luck is the only 6803 based game which uses it.

At power up, the Cheap Squeak's LED will flicker briefly, then flash, flash again, then turn on and stay on. Once the LED stays on, it seems to turn itself off for certain sounds, and then turn back on. Likewise, it appears to idle with the LED on, when no sounds are playing. The LED May turn on and off when sounds are playing or idle, but this is not always the case.

With Lady Luck, upon pressing the self test button (SW1), the sound board will play an explosion type noise. The board will then reboot itself.

Board Theory of Operations
The 6803 (U1) microprocessor multiplexes A0-A7 with D0-D7, calling those signals AD0-AD7. The processor fetches information from the sound ROMs (both code to execute and sound clips) by placing address information on AD0-AD7 and strobing the processor's AS (address strobe) signal to the 74LS373 (U2), thereby latching the lower 8 bits of the address bus in the LS373. A8-A15 are used along with jumpers JW1 through JW12, to implement a memory mapped I/O scheme to address the 2 sound ROMs which can be 2532s, 2732s, or 2764s. A14 and A15 control the 74LS10 (a triple 3-input nand gate) to assert device selects to the ROMs.

Note that the processor does not use the traditional R/W signal as it never "writes" to memory. Besides placing instruction address and data on the address and data busses, the processor reads sound selects via P20-P24 and writes sound data to the DAC via P10-P17. Think of these lines as PA1-PA7 of a 6821 or 6532.

The 6803 is initialized by the MPU at power up into 6803 mode N. Once initialized and running, the sound ROM code running in the 6803 accepts sound signal commands and merely reads pre-formatted sound "clips" from the sound ROMs and then writes the data to the ZN429 (U6) digital-to-analog converter (DAC) 8 bits at a time. The DAC converts the digital data to an analog level which is presented to the amplifiers for output to the speaker(s).

The board creates 5VDC on board by regulating 12VDC down to 5VDC. Unregulated 12VDC enters the board at J1-10. It is filtered by C8, C9, and C10. The inductor at L1 smooths the voltage somewhat. D6 (VR332, equivalent to a 1N5402), D7, and D8 drop the voltage by .5 - .7 volts (normal voltage drop across a diode). The 7805 at U9 further regulates the voltage down to 5VDC which can be measured at TP2 (TP3 is ground).

This 5VDC is used as a reference voltage by the amplifiers as well as to power the TTL logic ICs. The ZN429 DAC also uses this 5VDC as a voltage reference. To prevent the sound volume from fluctuating over the range of operating temperatures, the reference voltage is held constant by a "voltage divider biasing circuit" comprised of resistors at R22, R23, and R24, and a 2N5305 NPN transistor at Q7. This reference voltage is presented at pin 5 of the DAC.

Test Points

• TP1 should measure about 11VDC.
• TP2 is 5VDC.
• TP3 is ground.
• TP4 is the clock signal, provided externally by the 6803 for the purpose of synchronizing address and data read cycles.
• TP5 is the reset signal, which is also present on pin 6 of the 6803.
  

Bally Cheap Squeak Sound Board with Jumpers Highlighted

Jumpers JW2, JW4, JW7, JW10, and JW11 should be installed when U3 EPROM is installed for Lady Luck.

3.3.2 Turbo Cheap Squeak (T.C.S.)

The Bally Turbo Cheap Squeak (T.C.S.) Sound Board. Note that the headers, which are normally individual pins soldered directly to the board, have been replaced on this board. The test switch is also broken on this board.

The Turbo Cheap Squeak sound board was used on games like Strange Science and Motordome. The sounds it can produce are pretty basic.

The board features a 68B09EP processor, a 6821 PIA, 16K of static ram, and 256K of ROM. It interfaces to the MPU similarly to the Bally Squawk and Talk board. Volume is controlled by the pot at VR1.

Note that the board is marked "T.C.S. FOR PINBALL". Some Bally / Midway video games also use a Turbo Cheap Squeak sound board. The T.C.S. sound boards used for video games and pinball are not 1-to-1 compatible between one another.

The following games use the Cheap Squeak:

• Motordome
• Black Belt / Karate Kick
• Strange Science
• City Slicker
• Hardbody

Normal boot up diagnostics via the LED for the T.C.S is as follows:

• 1st Flash - Determines if the external ROM (U7) is good.
• 2nd Flash - Checks if the external RAM (U6) is good.
• 3rd Flash - Checks the 6821 PIA (U8).

3.3.3 Sounds Deluxe

Bally Sounds Deluxe Sound Board

3.4 Accessing Bookkeeping, Settings, and Diagnostics

6803 coin door test button

3.4.1 6803 Keypad

File:D&D keypad.jpg

The beloved 6803 keypad

As easy as "A, B, C".

4 Problems and Fixes

4.1 Power Problems

This is a stub

4.2 MPU Issues

4.2.1 Relocating the Factory NiCad Battery off the MPU

The factory NiCad battery has been removed, a blocking diode has been added, and long leads provided so that the remote holder can lie comfortably in the bottom of the head.

Like other Bally and Stern MPUs that employ a battery on the MPU to provide power to the volatile RAM, it's a good idea to remotely locate the battery. The 6803 MPU provides an excellent place to locate a blocking diode so that the MPU charging circuit is blocked from attempting to charge the alkaline batteries. In the picture at left, two holes were drilled in the fat trace leading from the positive battery connection to the northwest. That trace was severed under the diode where the black line is shown, and the diode soldered across the severed trace with the banded end pointing away from the positive connection on the board. Be sure to provide enough wire to allow the remote holder to reach the bottom of the head making it impossible for leaky batteries to drip on the circuit boards.

4.2.2 Leon's 6803 CPU Repair

Leon's 6803 repair procedure has been added to the PinWiki, and can be found here: http://www.pinwiki.com/wiki/index.php?title=Leon_Borre_Bally_6803_repair

4.2.3 Replacing header pins

Original headers shown on left...new header on the right. Note the damage to the plating on the old pins.

Bally 6803 header pins are different from every other game system header pins. Bally used pins without a "carrier". Over time, the plating on these pins fails, creating conductivity issues. These header pins can be replaced fairly easily. Simply heat each pin individually and remove them. It's best to heat the pin itself vice the pin/board junction as quite a bit of heat is required to remove the pins, which are "jammed" into the board. Installing a new strip of .100 pins may require a bit of tapping with a hammer as the new pins are larger in diameter.

Replaced .156 headers on a Bally 6803 MPU.

The same procedure may be used for .156 header pins on the MPU, as shown at left.

4.7 Sound Problems

4.7.1 Sounds Deluxe Board

Bally Sounds Deluxe Sound Board

This sound board has a common problem with DAC failure. AD7533 chip is easy and inexpensive to replace. You can prevent failure by removing C12 (47 uf) capacitor. It seems to have no adverse affect but prevents a voltage condition on power down that can destroy the DAC.

The LED with flash a check sequence on power up. 6 Flashes ROMS and RAM are OK.

4.9 Coins Register But Don't Credit Up

This is commonly seen on VPinMAME emulation, but applies to real life as well.

Coins drop OK, switch is good, game makes noise, but it remains on "Credits 0" and doesn't credit up.

Symptom is corrupted/blank NVRAM.

To fix, open coin door (make sure coin door switch is working, otherwise the keypad won't work), then do these steps:

Hit "Test", to enter operator mode.

Hit "A" until "Feature Options" is displayed.

Hit Enter.

It will say "Reset Factory Is".

Hit 6, then 5, then Enter.

Hit "Game" to return to attract mode. You'll know it worked because it will take longer than usual to reach attract mode, and the display will flicker slightly as the computer clears the memory (this is normal).

Intuitive and easy to remember, right? And Bally had the nerve to advertise "manual-free testing"....

5 Game Specific Problems and Fixes

Example would be servo controller on Independence Day pinball

6 Repair Logs

Did you do a repair? Log it here as a possible solution for others.