Atari’s BattleZone game is considered the first real 3D video game. I did the 3D graphics algorithms and the hardware sounds.

This board produces the BattleZone Engine sound using the same circuit I designed for BattleZone except that the engine speed is controlled by a pot instead of a single bit.

What?

If you have played the original BattleZone you might not have noticed that the engine has only two speeds: Idle and Fast. That is because I had only one hardware bit to control the speed. I used an RC circuit to ramp the voltage up and down to a 555 timer.

In this one I used an actual pot. You can use a Trimpot at R20 or a Real Pot (not both). If you use a Real Pot you will have to connect it to the circuit with wires. (There are only three wires.) If you want you can control it with your own voltage (0 - +5V). Trimpot R17 sets the idle frequency.

To do the engine sound I used two counters with different cycle rates. One divides by 10, the other divides by 12. Then I add several of the bits together. As you increase the frequency the difference frequency increases. That is what why the throbbing sound gets faster with engine speed. The two counters in the BattleZone schematics are ICs F4 and F5 (LS161).

I could have done it with a microcontroller such as the Texas Instruments MSP430G2xxx series but then it would have just been a sound from a sound chip.

What can you do with the BattleZone motor other than to play with it for a few minutes?

1. Put it on a bicycle with a speed sensor. Add a speaker. The board has an LM386 speaker driver which is good for a few watts.

2. Put it in your electric car. Some time in the 1990s I was walking in a parking lot past a car that I realized was unusually quiet even though it had a gas engine. It was a bright sun-shiny day and if it had backed up I might not have noticed the backup lights. Now there are electric cars that are totally quiet. They (the government) could require electric cars to have a backup beeper but do you want your expensive electric car to sound like a garbage truck? How about a BattleZone tank instead, especially if you have a loud sound system with the bass turned up? You can use a speed sensor or control it manually. You can gun the engine when someone walks by. That works too when you are moving forward behind someone. You don’t have to use it all the time, just at slow speeds when pedestrians are around. Use it when you are driving slowly past an elementary school when the kids are out on the playground. That might be fun for everyone.

If you are not already a Maker (and you want to be one) see my tutorial on Making Things at www.jmargolin.com/making/jm_making.htm

Jed Margolin

BZ_DP-156_2nd_Printing.pdf