How to Install RPU

Install Rev 4

At the top of the Rev 4 board (on the back), you’ll find a set of Female header pins that will plug into J5 of the MPU. It’s important to note that pin 1 of J5 is all the way to the right. Whenever you install a Rev 4, be sure that the rightmost pin of the Rev 4 connector aligns with the rightmost pin of J5.

If you’re installing on a Bally MPU (AS-2518-17 or AS-2518-35), or a Stern MPU100, you’ll also have to install a jumper to pick up the IRQ signal from the board. There’s a pin on the lower-left corner of the Rev 4 labelled “J1 / IRQ”. With a jumper wire (I usually use an alligator clip wire), connect that pin to the top leg of R134. You’ll find that resistor (R134) just under the U11 PIA chip on the MPU.

If you’re installing on a Stern MPU200 or an Alltek replacement, you don’t need a jumper.

If you’re attempting to install a Rev 4 on a Weebly, STOP! The Rev 4 isn’t compatible with the Weebly. You can plug an Arduino directly into the latest Weebly board (see https://nvram.weebly.com/ for more information), or you can use a Rev 102 (below).

Install Rev 102

The Rev 102 board plugs into the processor socket of an MPU. The Rev 102 is compatible with any MPU that runs with an Motorola 6800, 6802, or 6808 CPU. This includes Williams MPUs (up to 11c), Bally, Stern, Atari, and Data East.

First, you need to locate the program CPU processor. For most MPUs, the program CPU will be the only Motorola 6800/6802/6808 processor on the board. However, starting with System 9, Williams was putting two CPUs on the MPU—one for the program and one for the sound. Data East followed suit. So, for those boards, you have to determine which CPU socket you need to use.