Table of Contents

  1. What is the purpose of The Ultimate MPU Board?
  2. What is the suggested application of The Ultimate MPU Board?
  3. Why is The Ultimate MPU Board half size?
  4. Why did you use a Programmable Logic Device (PLD)?
  5. Why do you provide a selectable clock speed jumper?
  6. How did you manage to make The Ultimate MPU Board compatible with Stern MPU 200 series?
  7. How do you plan on documenting/supporting your products?
  8. What is the use of the capacitor/resistor networks?
  9. How do you switch to free play Bally version?
  10. How do you switch to on-board diagnostics?
  11. Will the Ultimate MPU work with a "Baby Pac-Man" or "Granny and the Gators"?
  12. How does the Ultimate MPU automatically work with both zero-crossing circuit types?

What is the purpose of The Ultimate MPU Board?

We set out to make The Ultimate MPU Board fit several needs.  Our first goal was to produce a MPU board that could handle all of the different versions of MPU series boards that both Bally and Stern manufactured between 1975 and 1984.  Another important goal was for all of the games, including free play versions to be installed on one board eliminating EPROM changing.  We wanted the new MPU board to have a dipswitch for easy switching between the different games and to eliminate any complicated jumpering system.

An additional goal was to make a board that would satisfy the replacement needs of both operators and homeowners/collectors.  The consideration for the operator is that they need a MPU board that is rugged enough to run 24/7. The need for the homeowner/collector is a board that can be easily installed and set up and then can be used for years to come with out concern. How else could we offer a lifetime warranty no matter if your using our board for business or pleasure.

Last but not least, one of our goals was pricing. Make a board that can sell for under $200.  Also we wanted to be able to offer distributors/operators attractive quantity discounts making the need to repair old damaged MPU boards a thing of the past.  Check out our article on Repair or Replacing?

We believe that we have accomplished all of the above goals.

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What is the suggested application of The Ultimate MPU Board?

We have designed the board to be a universal replacement board to be used in either a commercial or home environment.  That's why we can offer a lifetime warranty no matter if The Ultimate MPU Board is used in the home or business.

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Why is The Ultimate MPU Board half size?

The size of the original board was based upon mid 70's manufacturing techniques and then available components.  We chose to make the board as small as possible without requiring any modifications for mounting. The mounting rails have 6 holes, four holes in the corners and 2 in the middle. What we chose to do was use the lower four holes.  The existing cables reach without any strain.  This physical reduction in size reduced the cost of the printed circuit board in half, enabling us to pass the savings on to you, our customer.  Our board also has less components which most importantly use less space, meaning less power.

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Why did you use a Programmable Logic Device (PLD)?

By using a PLD, we were able to make the switching of different games as easy as using a dipswitch.  This will allow anyone that is not comfortable with electronics to be able to change to any one of over 90 preprogrammed different games.  The PLD contains complex logic that eliminates the need for jumpers and reduces the overall component count.  Better yet, no more changing of jumpers or unsoldering wires to change a MPU board from one game to an other.

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Why do you provide a selectable clock speed jumper?

This jumper will allow you to switch from a 500Hz clock rate to a 1Mhz clock rate that is used by the Stern's MPU 200 series. Many Bally pinball machines will not operate correctly at 1Mhz clock speeds.

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How did you manage to make The Ultimate MPU Board compatible with Stern MPU 200 series?

By allowing the board to have a jumper for the clock speeds and using our Programmable Logic Device is such a way to make up for the (2) 5101 chips that were used on the original Stern MPU 200 series boards.

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How do you plan on documenting/supporting your products?

We feel very strongly about making this an open product.  That is why we have posted on this web site the schematics, board layouts, manuals and pictures of our products, free of charge.  We will continue to update our documentation and support as needed.  As for support, you can contact us by either phone or email.  We understand that you might have other questions about your game even after purchasing.

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What is the use of the capacitor/resistor networks?

Resistor and capacitor networks are more cost effective.  They reduce the overall component count, and reduce the overall size of the board.  This allows us to manufacture a board for less.  The networks also provide a filter that protects the sensitive components from static and the inherent electrical noise found in a pinball machine.

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How do you switch to free play Bally version?

This is accomplished using the game option dip switches.  Setting the game select switch to the free play mode for whatever game you have enables the free play mode.  For simplicity, the free play mode is the same as the regular mode except SW1 (leftmost) on the Game Select dip switch is on.  Once the free play mode is enabled, turning off the credit display dipswitch activates this feature.  See our manual for more detailed info.

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How do you switch to on-board diagnostics?

On-board diagnostics are enabled when the SW1 and SW2 of the Game Select dip switch are on.

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Will the Ultimate MPU work with a "Baby Pac-Man" or "Granny and the Gators"?

YES, these games used a -133 MPU board.  In these games the zero-crossing signal is derived from the GI buss rather than the solenoid bus.  The Ultimate MPU works with both versions automatically making it universal.   

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How does the Ultimate MPU automatically work with both zero-crossing circuit types?

Both are very similar, the only difference is that the GI powered zero-crossing circuit needs a rectifier in series because the GI bus is an AC voltage.  The solenoid voltage is already rectified by the bridge rectifier located in the power supply, therefore a series diode rectifies the GI voltage and passes the solenoid voltage creating the automatic zero-crossing detector circuit.  What does all this mean to you,  just plug in our board to a listed game and you will not need to worry about modifying a game board ever again.

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Copyright 2007  [www.allteksystem.com]. All rights reserved.
Revised: 08/20/07.