Did you build your own version of 6.00.02RC15 for the PicoCalc? If there’s a repo somewhere, then it might make sense for others to use it too, especially if you’ve managed to fix the keyboard disconnect issue and still keep all the PicoCalc support (for display, keyboard, etc.) in.
I’m not sure what has changed from RC9 to RC15, but I guess the built in limits for overclocking was something that changed. They have separate values for different configurations too, like the HDMI and USB stuff, and I’m not sure what any of that is based on since it’s all running on the same Pico processors. Maybe there are weird timing issues depending on what other hardware is connected? Or maybe it’s all just arbitrary. The values in the code don’t really explain why they are different or changing in different releases.
(Also, they should probably update the manual to match those new values at some point, and maybe explain what they are based on. No real reason to bother with it for the RCs since I doubt many people are using them since it’s bleeding edge, but for a new proper release hopfully that stuff will be in sync.)
The simplest solution for playing mp3 is something like this
Option cpuspeed 200000
Play mp3 “b:mp3dir”
And that’s it
And no, nothing happens to your pico to run at 360000, mine is running for weeks that way and not even gets warm.
And yes, if you only give the directory, mp3s plays in order one after other and you can control it with:
Play next
Play previous
Play pause
Play resume
The name of the track is mm.info(track)
And yes, I am running MMBasic V6.00.02RC7
Read the page 137 of the manual, (at the bottom)
Best regards.
P.S. in my SD only plays 20 songs, but I am not sure why, could be memory or the SD or something, please post your results.
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How do you set the CPUSPEED higher than 252000? When I try with WebMite MMBasic, I get an error saying the maximum is 252000. Also, why do you set the CPUSPEED to 200000 before playing an MP3? The Raspberry Pi website says speeds higher than 260000 will damage the WiFi/Bluetooth interface chip.
Ooh, I think it is because they are talking about the 2040, I have the 2350, and for playing mp3, you must set to minimum 200000, It is all on the manual,
With varous builds and cpu speeds, both pico and Pico2 I’ve had zero luck playing the supplied mp3 !. Yes even the magic 200000 cpu speed yet I always get “Error : mp3 init”
Any ideas ?, unable to transfer other mp3’s to the sd card for a day or two…
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Are you running on a pico or a pico 2? I have a pico 2 and it works fine there.
Looks like this might be a problem with the newer builds based on this:
If that’s the case it makes sense that people running older builds wouldn’t have the problem.
I’m running the RC19, which was published yesterday, set speed to 250000 and don’t have that problem either. Again, on a pico 2.
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PicoMite_PICORP2350_V6.00.02RC20.uf2 by adcockm. @300 Mhz
Included mp3 file “Error : Mp3 init”. Tried 3 others (all 128Kb/s files as have none lower). Two worked, one gave the error 
. Will look at file differences asap. Quality headphones (4 ring with mic) work too and surprised the quality is ok 
, definitely stereo.
Seems the mp3 playback issue is related to the encoder originally used to create the file. Initial look shows the failing included file (BellLabs_Fine bitrate 64/24000) is “Lame 3.96” yet two of mine that work fine (bitrate 128/44100Hz) are ‘Fhg’ and ‘Xing’ encoded…
(Using Pico2 @300Mhz, PicoMite_PICORP2350_V6.00.02RC20.uf2 by adcockm)
I have the same issue than you. I have working the PicoCalc MP3 Player, but only works the right channel. Anyone has stereo output? I was trying to use PicoMite but I have the “Only available with VS1053 audio” error. But my main concern is the stereo output.
The problem with stereo output on the PicoCalc is that the two pins that the PicoCalc ties to the left and right channels are on the same PWM slice, so when using PWM to generate audio you can’t set the frequency independent of one another simply by adjusting the clock. Apparently you can get around this with things like wavetable synthesis, but I haven’t tried this myself.
Thanks for your quickly response. Well, but that means that in theory using a different board, for instance ESP32 Pico, or LuckFox with Linux, maybe these board can handled it? it isn’t it?
Yes. Unfortunately, though, there are more serious problems with using a Luckfox Lyra for audio, because to generate audio on both channels with it you need to conduct a bit of surgery, as reported elsewhere on this forum.
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The PicoMite RP2350 will play stereo MP3 files. The RP2040 isn’t fast enough to decode at 44.1KHz stereo. The PicoMite REQUIRES the left and right channels to be on the same PWM slice.
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And don’t even try to do 44.1 kHz MP3 playing on an RP2040 without seriously overclocking it. People have tried and failed to do this. The pretty much unanimous conclusion is that it cannot be done.
I don’t know, but with the Pico Mp3 Player and my original RP2040 (PicoCalc), that was working, I mean, mp3 files at 2ch 44100Hz was working (but mono of course)
I noticed this when I had the volume knob set at minimum. Increasing the volume knob fixed the problem.
