I'm playing with a PicoMite VGA/PS2 that has a RP2350 Pico 2W as the processor board.  

One of the things that I have been fighting is the setup of an SD card with a few games.  I have had to go through Petscii Robots, for example, and comment out all of the sound calls to get the game to run.  It returns "Error:Audio not enabled" on every sound call line.  I'm happy to have the game running, but sound would be awesome!

Has anyone designed and implemented an audio output circuit for this reference design?

My electronics knowledge and assembly abilities are passable, but circuit design and implementation is beyond my knowledge level.

Welcome to the Shed :)

There could be several reasons. Can you provide us with a link to the board that you are using please?

You probably haven't got OPTION AUDIO set correctly. The settings depend on the audio hardware that is available on that particular board.

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Edited 2026-08-29 17:00 by Mixtel90

The standard VGA design Uses



This outputs pwm audio on these pins. Circuits are plenty on this forum. But just defining this is sufficient to run many games without listening to the sound.

Petscii robots plays MOD files. You also need.



Volhout

P.s. You probably have the original silicon chip magazine design, that does not provide audio output.
Edited 2026-08-29 17:43 by Volhout

G'day RDuckey,
If you have the early VGA/PS2 board as shown in the PicoMite manual:



As suggested above, it will probably be easier to simply set OPTION AUDIO GP6,GP7 so the PicoMite thinks it has audio and you can run the games until you have the audio circuit built.

The circuit in the manual is suitable for simple sound effects etc using PWM but if you want to play music etc or use an external amp then a DAC is lightyears better. Check out the circuits posted recently under the Home Made Pico Computer 3 threads.

Hope this helps,

Regards, Lyle.

Hi RDuckey!
I built a low-pass filter for this PICO board based on instructions from an older manual. You just need four 2.2k resistors, two 1k resistors, and two 47nF capacitors. Here are the instructions:






I use option audio gp6,gp7.

I also bought a small amplifier module from AliExpress for it—search for "PAM8403 5V Power Audio Amplifier Board."

I mounted the whole setup on a perfboard and added two small speakers. I use it for games on the VGA-PICO; FROGGY sounds just like it does in an arcade. I think the sound quality is very good. For playing music, other solutions would certainly be better.







Edited 2026-08-29 19:49 by v.lenzer

See this

https://www.thebackshed.com/forum/ViewTopic.php?FID=16&TID=17615#232413

Specialiteit designed sound output for that board.

Volhout
Edited 2026-08-29 22:57 by Volhout

I am indeed using the original design from Geoff G.  Thanks for the information that was provided by all.

I had guessed that the outputs would have to go through an amplifier similar to the one referenced by v.lenzer, but knew nothing about the low pass filter and the rest of the circuit.  Thanks for that.  An order from AliExpress is on its way.

Volhout - The design from Specialiteit looks like a little too much, although rather elegant in its dual purpose, I am not interested in a clock. I just wish it was through hole instead of surface mount.

Lyle - I will have to go poke at the threads for the Home Made Pico Computer 3.  I had skipped them, thinking they would be more advanced than needed.