Williams Pinball Controller

The Williams Pinball Controller (WPC) is an arcade system board used for several pinball games designed by Williams and Midway (under the "Bally" name) between 1990 and early 1999. It is the successor to their earlier System 11 hardware ("High Speed", "Pin*Bot", "Black Knight 2000"). It was succeeded by Williams/Midway's Pinball 2000 platform, before Williams left the pinball business in October 1999.
"FunHouse" (designed by Pat Lawlor) was the first production game to use WPC, although there are prototype Dr. Dude machines that use WPC.
Variations.
There are six variations of the WPC hardware. The original version is sometimes referred to as WPC-89. The WPC MPU remained the same through all generation up to the addition of the security chip in WPC-S, and then the subsequent WPC-95 board. The variations are as follows:
WPC (Alphanumeric).
Some "Dr. Dude" machines were also made using this WPC generation, although most were made using the later System 11 board.
WPC (Dot Matrix).
"" was the first to be designed with a dot matrix display, but was released after "Gilligan's Island", due to Terminator 2 having a longer development time than "Gilligan's Island".
This generation WPC hardware was also used in some of Williams / Midway's redemption games ("SlugFest!, Hot Shot Basketball") as well as in the first Shuffle Alley Game Strike Master Shuffle Alley - 1991.
WPC (Fliptronics).
"The Addams Family" was the only game produced with the Fliptronics I board, which is compatible with Fliptronics II boards, which added a bridge rectifier for the flipper voltage.
WPC (DCS).
"Twilight Zone" was designed to be the first pinball machine to use the new DCS system, but due to delays of the new hardware design it was decided to release it on the old hardware (using downsampled sound effects) instead. The redemption game "Addams Family Values" also used the DCS Sound System.
WPC-S (Security).
Starting with "World Cup Soccer", a security programmable integrated circuit (PIC) chip was added to the CPU board in all WPC-S games at location U22. This PIC chip was game specific making it so CPU boards could not be swapped between different models without changing the security PIC chip.
WPC-95.
In this final revision of the WPC hardware, the dot matrix controller and the DCS sound boards are combined into a single A/V board, while the Power/Driver and the Fliptronics boards are combined into a single Power/Driver board, bringing the board count down to three boards. It also includes the same game-specific security PIC introduced in the WPC-Security system.
This generation WPC hardware was also used in the Midway redemption game "Ticket Tac Toe", March 1996 and the Shuffle Alley game League Champ Shuffle Alley, 1996.