Williams System 3 - 7

Note: This page is a work in progress. Please help get it to a completed state by adding any useful information to it.

1 Introduction

Williams entered the SS (Solid State) era with a conversion of a 1976 Williams EM (Electro Mechanical) [ed note: maybe someone can show me how to link to a glossary page with SS EM etc on it - We need a glossary!!!?] pinball game called Grand Prix.

It is thought that 4-5 games were converted to solid state prototypes using the new System 1 MPU and digital displays.

Next was a 10 unit run of another 1976 EM game called Aztec. Aztec is considered to be System 2 and is also very rare. Both System 1 & 2 happened right at the end of 1976. It was a hybrid machine still retaining the EM chime unit in the cabinet for sound and a credit window and EM reel behind that on the backglass. The player scoring was digital.

System 3 games were the first Williams production games, starting with Hot Tip in Nov. '77 and ending with Disco Fever in Aug '78. There were based on the Motorola 6808 CPU and using an MC6820 PIA (Peripheral Interface Adaptor) to handle the Display I/O from the MPU board. They also had three other 6820 PIAs (the same type) on the Driver Board for the Switch inputs and the Lamp and Solenoid outputs (Solenoid drives were mainly for the Coils at this point, a few triggered sound calls). [ed note: This needs a slight re-write but the info is basically there].

Later on Williams moved to using the updated 6821 PIAs, but the separate driver board remained almost completely unchanged right through to System 7. After System 7 they combined the MPU and Driver Boards on a single PCB (Printed Circuit Board) and removed the problems associated with the now infamous Williams "40-way" connector.

During System 3 (Phoenix, Disco Fever) a memory protect circuit modification was added as to help protect CMOS RAM data during power up and power down of the game. DIP switches were still being used to set game settings (such as # of balls per game, high score replays).

System 4 games ran from Pokerino in Nov '78 through to Stellar Wars in Mar '79. A notable game just before Stellar Wars was Flash (another Steve Ritchie designed game and one that outsold all of the other System 4 games combined with a production run of 19,505. During System 4, Williams moved from using DIP switches to change game settings to having the game settings changed from the coin door switches. The settings were still stored in battery protected CMOS RAM. [ed Note: Citation needed ? - I'm fairly sure this is accurate] A coin door interlock switch enforced that CMOS memory could not be modified unless the coin door had been opened by the operator. Some of the game audits (coins accepted, total number of games played, etc.) still could not be changed without access to the MPU board behind the backglass.

System 6 games ran from Tri-Zone in Jul '79 to Scorpion in Jul '80. two notable games from this era were from the end of '79 and the beginning of '80 Gorgar and Firepower. Gorgar (14,000 produced) was the first talking pinball, and Firepower (17,410 produced) both talked and introduced the 'Lane Change' and 'Multiball (tm)' features to SS games. Note that there had been muliball play available in EM games, this is a common misunderstanding. The features these games introduced became standards on almost all pinball games produced to right up until today.

Technically, System 6 was not a huge jump from System 4, although more ROM memory could be addressed and this was used to hold increased game code on Firepower. It used a 2716 Game ROM (2K) which was standard, plus 3 x Harris Bipolar Proms (512 bytes each) giving a total game code size of 3,584 byles. 3K of code space is hardly anything by today's standards.

System 6a deserves to be mentioned here as it marked a transition to System 7. The game Alien Poker from Oct '80 used the Syatem 6a MPU board (which was not very different from System 6). But it supported 7 digit scoring displays and a redesigned Master Display Driver board, located behind the backglass on the back of the 'Lamp Board'. It also used a special 4 digit "credit/match" display in the approximate position where the System 6 Master Display Driver had been showing the same information (on a 6 digit display, with 2 of the digits unused). This new 7 digit scoring displays with a 4 digit credit/match display were then used in all the System 7 games (and System 9).

System 7 games ran from Black Knight in Nov '80 through to Star Light in Jun '84. Complete System 7 Game list

Black Knight (13,075 produced) introduced a two level playing field and Magna-Save (tm) where the ball could be stopped from draining down the sides by pressing a cabinet button that activated an electromagnet. Star Light (100 produced) was almost a 'botique' game by Williams' standards as the focus was then on System 9 and prodiction of Space Shuttle. At least one Star Light game was used as a Prototype for System 9.

System 7 was considered a step change. It had a redesigned MPU board, now supporting a single 7-segment display for improved diagnostic information, instead of the original 2 LEDs that system 3-6a had used. It also added commas to the player scoring displays and moved the sound select support to the MPU board. An extra 6821 PIA supported both the sound/speech selects and the display of commas. This freed up five Solenoids at positions #9-13 from sounds to be able to drive extra coils (or Flashlamps). As mentioned previously, the Driver Board remained the same, except for 8 resistors that changed to zero-ohm jumpers in the switch matrix inputs. The sound and speech boards were also unchanged since introduced for Gorgar.

System 8 was used on a single game Pennant Fever in May '84. This was a 2 player 'Pitch and Bat' game with men running round bases. It was the first solid state 'Pitch and Bat' that Williams produced. System 8 was never used for pinball games.

2 Games

2.1 System 3

• Contact
• Disco Fever
• Hot Tip
• Lucky Seven
• World Cup

2.2 System 4

• Flash
• Phoenix
• Pokerino
• Stellar Wars

2.3 System 6

• Blackout
• Firepower
• Gorgar
• Laser Ball
• Scorpion
• Time Warp
• Tri Zone

2.3.1 System 6A

• Algar
• Alien Poker

2.4 System 7

• Barracora
• Black Knight
• Cosmic Gunfight
• Defender
• Firepower II
• Hyperball
• Joust
• Jungle Lord
• Laser Cue
• Pharaoh
• Solar Fire
• Star Light
• Time Fantasy
• Varkon
• Warlok

3 Technical Info

Things like Data East's controller board was a copy of William's System 11 with some changes would go here. *this is an example that doesn't apply to this page

4 Problems and Fixes

4.1 Power Driver Issues

This may not apply to some, as MPU might have been part of it.

4.4 Display Driver Board

Possibly doesn't apply to some, can't think of an example.

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.