Could I get help with a mod to convert my paddles to digital pots?

[Williamstrock]

I'm an amateur tinkerer so I can solder a bit, but reading schematics is still foreign to me. It looks like it should be possible to have a digital pot control the analog pot in the paddles without an Arduino. I'd really like to know what materials to buy and how to go about doing this. Any help would be appreciated.

 

Thank you

[+Stephen Moss]

14 hours ago, Williamstrock said:

It looks like it should be possible to have a digital pot control the analog pot in the paddles without an Arduino.

What exactly are you trying to do here? If you are trying to replace the analogue pots with digital pots for use with the 2600 that will not work.

A digital pot (assuming we are talking about the IC) acts as a potentiometer and so outputs a variable voltage. However, the 2600 uses the analogue pots as variable resistor (not as a potentiometer) that varies the amount of current used (and therefore time taken) to charge a capacitor.

There is no direct correlation between the two methods, with a Microcontroller you can potentially read the voltage of an analogue potentiometer, use that to calculate its resistance and then calculate and set the appropriate output (can't remember if the paddle read is voltage or timer triggered) at the appropriate time, but to me that is a lot of pointless time and effort compared to just using an analogue pot as originally intended.

 

14 hours ago, Williamstrock said:

reading schematics is still foreign to me.

That could be a bit of a problem as any solution someone gives you will probably involve a schematic of the circuit. 

[Williamstrock]

I bought a Retron 77 and some oem paddles. After cleaning the paddles they still have jitter. I called Retron and was told that the system doesn't handle the old pots well and that I should go with a digital solution like their ranger controller. I'd rather not spend $25 a piece on their controllers. I'll buy a couple 2600-dapters if I need to. I'm trying to cut down of costs and if it's doable I'd like to mod my paddles.

 

Thanks for the reply

Edited July 17, 2021 by Williamstrock
Redundancy

[Williamstrock]

I'm just gonna get a couple 2600-dapters. I emailed them and they confirmed that I can do 4 player paddle games with two adapters barring any sort of unknown issue with the Retron 77, and mine is running the community build of the newest release of Stella.

 

I would still like to see this project get done though. While researching it I found old AA post talking about considering the same thing. Someone should do it. Or walk me through it and I'll do it. I'll buy a new set of paddles just for this and we could team up and get a tutorial video done or something. It would be good practice for me, and would be something other Retron 77 owners might be interested in.

[ChildOfCv]

I suppose a microcontroller could be used to perform this.  You'd have one output pin with a 1K resistor.  It connects to an input pin and to the paddle input.  Finally, it has a sensor from the digital pot.  Operation would be:

 

Output goes high.  When Atari resets to get paddle position, this brings its trigger input low and it turns off the output.  Output waits for a period of time according to digital pot, then turns back on.

 

This allows it to respond to the Atari's paddle dumper.  But instead of a sawtooth rise like you'd normally see with paddles, it just sits low until trigger time and then suddenly charges up.

Edited July 18, 2021 by ChildOfCv