JUMPER COMBINATIONS for STERN MPUs

From 1977 until 1984, Stern used only two circuit boards as the main processor unit (or MPU board) in every model of their pinballs. From 1977 through 1979, this board is designated the MPU-100 or 'early' board. All of these early games used a U2 & a U6 as GAME ROMS. The following games were shipped from the factory with early MPU boards:

• Stingray
• 'Pinball'
• Stars
• Memory Lane
• 'Lectronomo
• Nugent
• Dracula
• Wildfyre
• Trident
• Hot Hand
• Majic
• Genisis Shuffle

These games can be made to run on any Stern or Bally MPU board, early or late.

Beginning in 1979, Stern expanded the capability of their MPU board and introduced the MPU-200 or 'late' MPU board. This board looks very much like the MPU-100, except that it has an additional 5101 RAM chip added at the bottom of the board. The MPU-200 board is capable of running every STERN game AND every BALLY game of that era, early and late.The following list shows the STERN 200 series games. These games all used 4 GAME ROMS labeld U1, U2, U5 and U6. THESE GAMES WILL ONLY RUN ON THE MPU-200 BOARD! THEY CANNOT BE MADE TO RUN on the early MPU board!

(This list is in alphabetical order):

• Ali
• Big Game
• Black Beauty (No U2 chip used!)
• Catacomb
• Cheetah
• Dragon Fist
• Flight 2000
• Free Fall
• Galaxy
• Iron Maiden
• Lightning
• Meteor
• Nine Ball
• Orbitor
• Quicksilver
• Seawitch
• Split Second
• Star Gazer

Both the early and the late MPU boards use JUMPER wires which can be moved to change the way that the processor chip addresses the information contained in the ROM chips. These READ-ONLY-MEMORY chips contain the maps of the playfield and the switch matrix, the layout of the solenoid coils, as well as the 'rules of the game'. When these games were first produced, it was cost effective to have the ROMs produced in large numbers with the program imprinted permanently on the chip. These devices, called MASKED ROMS, can not be erased or re-programmed. They require a particular JUMPER combination to run. If any one of the jumpers is missing or misplaced, the board simply will not work. To confuse matters, it is now possible to purchase replacement ROMs on EPROM, or ERASABLE-PROGRAMMABLE-READ-ONLY-MEMORY. The only difference between the MASKED ROM and the EPROM is the ADDRESSING neccessary for the computer to read the chip. Therefore, it becomes neccessary to change the JUMPERS when changing chips, whether you are putting a different game on a particular board, or simply replacing failed original chips. The folowing JUMPER CHART explains how to get any particular device to run in any given MPU board. Note: Stern ROMs labeled "25A-ROMP#" are 9316A masked ROMs. Chips with a 'window' on top are 2716 EPROMs. Both chips contain the same program, but they are selected differently, requiring that the proper 'jumpers' be connected on the MPU board to match the device type.

STERN 'EARLY' MPU-100 WITH:

*9316A in U2 9316A in U6 = Make jumpers 1-2, 3-4, 6-7 with no modifications.

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*2716 in U2 9316A in U6 = Make jumpers 1-2, 3-4, 6-7 and do the following modifications:

• Component side of board: CAREFULLY cut the circuit trace running from {U2 pin 18} to {U3 pin 18} where it passes between sockets U2 & U3.
• Solder side of board: Run a jumper from {U2 pin 18} to {U17 pin 11}. Cut the trace going to {U2 Pin 21}. Run a jumper from {U2 Pin 21} to {U2 Pin 24}.

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  *2716 in U2 2716 in U6 = Make jumpers 1-2, 3-4, 6-7 and do the following modifications:
• Component side of board: With a fine cutter, snip pin 4 away from the chip body of U18;
• Solder side of board: Short pin 4 to pin 5 on U18 with a solder blob. Then, on both U2 & U6, cut the trace at Pin 21 and run a jumper from Pin 21 to Pin 24.

STERN 'LATE' MPU-200:

• IF U1 IS A 9316A ROM, MAKE 8-9, 26-28

• IF U1 IS A 2716 EPROM, MAKE 9-10, 27-28
• IF U2 IS A 9316A ROM, MAKE 1-5, 2-6
• IF U2 IS A 2716 EPROM, MAKE 2-3, 5-7
• IF U5 IS A 9316A ROM, MAKE 19-20, 29-31
• IF U5 IS A 2716 EPROM, MAKE 19-21, 29-30
• IF U6 IS A 9316A ROM, MAKE 12-13, 22-25
• IF U6 IS A 2716 EPROM, MAKE 13-14, 23-25
• ALWAYS MAKE 16-18, 32-33, 34-35
• THEREFORE, TO RUN 4 2716 EPROMS IN U1, U2, U5, & U6 ON A STERN MPU-200 CONNECT THESE JUMPERS AND NO OTHERS:
  2-3, 5-7, 9-10, 13-14, 16-18, 19-21, 23-25, 27-28, 29-30, 32-33, 34-35 DO NOT USE 36, 37, OR 38.
  

Some interesting and little-known facts about the MPU-200:

If you power-up an MPU-200 with all 32 dip switches turned off (Open), it will flash 7 times and jump into self-test.To down-grade the MPU-200 to act like an MPU-100, remove jumpers 32-33 and 34-35 and pull the upper 5101.The MPU-200, when jumpered for 4 2716 EPROMS (U1, 2, 5 & 6), will run Bally (3) 2716 (U1, 2 & 6) games. To run Bally (2) 2716 games (U2 & U6), change 13-14 to 13-15 and change 5-7 to 1-5.

Pinball ROMs

Part number	Description	price	comments	location	Open a picture in a new window	BUY it NOW!
ROM	Programmed GAME ROM from our archives	$25. for any one chip	These are the 'personality chips' which contain the GAME PROGRAM	YOU NAME THE GAME! Available for MPU boards, sound boards, displays, ANYWHERE a programmable device was used in your game: WE KEPT A COPY FOR YOU IN OUR ARCHIVES!
RM2	Programmed GAME ROMs from our archives	$45. for two from the same game	set of 2	YOU NAME THE GAME!
RM3	Programmed GAME ROMs from our archives	$60. for three from the same game	set of 3	YOU NAME THE GAME!
RM4	Programmed GAME ROMs from our archives	$70. for four from the same game	set of 4	YOU NAME THE GAME!
RM5	Programmed GAME ROMs from our archives	$80. for five from the same game	set of 5	YOU NAME THE GAME!

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