Tandy1000TL wrote on 2024-11-09, 08:12:

Is there any way that Nuked SC55/emusc could be added to the McCake? That would be absolutely awesome to emulate both MT32 and SC55 in a native type of way, rather than utilising sound banks for the SC.

IIRC the SC-55 is a PCM synth, so it is only using soundbanks. Thus this would be completely redundant as the McCake can run the actual SC55 soundbank.

Matchstick wrote on 2024-11-09, 17:19:

Tandy1000TL wrote on 2024-11-09, 08:12:

Is there any way that Nuked SC55/emusc could be added to the McCake? That would be absolutely awesome to emulate both MT32 and SC55 in a native type of way, rather than utilising sound banks for the SC.

IIRC the SC-55 is a PCM synth, so it is only using soundbanks. Thus this would be completely redundant as the McCake can run the actual SC55 soundbank.

The "actual SC55 soundbank" that you are likely referring to has been sampled from a real SC-55 or other sources and compiled into a soundfont (SF2) . That soundfont is then used by a softsynth engine that implements general MIDI and at least some GS features. It may sound more or less similar to an SC-55 (depending on MIDI content) , but it is not an emulation of an SC-55 .

Nuked Sc-55 is an actual SC-55 emulator and uses both the original sample DATA and ROM code from an actual SC-55 and, from what I've heard and read, it sounds almost exactly like an SC-55 (it also emulates a few other Roland models). AFAIK, it is currently too resource intensive to run on a Pi4. I have no idea if it can be optimized enough to run on a Pi5, let alone a Pi4. I stand corrected Re: [RELEASE] Nuked-SC55, low-level Roland SC-55 series emulator announcement . Apparently, it can run on a Pi4

Tandy1000TL wrote on 2024-11-09, 08:12:

Is there any way that Nuked SC55/emusc could be added to the McCake? That would be absolutely awesome to emulate both MT32 and SC55 in a native type of way, rather than utilising sound banks for the SC.

I've wondered this too, it would be fantastic.

My McCake started giving me Low Voltage errors and outputting distorted audio after a few seconds of music. Any ideas? Floppy power is connected. Tried two (cheap) psus.

appiah4 wrote on 2024-12-14, 15:22:

My McCake started giving me Low Voltage errors and outputting distorted audio after a few seconds of music. Any ideas? Floppy power is connected. Tried two (cheap) psus.

Other than inspecting the board to see if you can spot anything that is up, I can only recommend reseating the compute module.

Other than that, reach out on the serdashop contact form and see if they have any other suggestions.

Reseating did not help. It works on my older PSUs when nothing else is attached but gives a voltage error as soon as a hard drive or optical is added. I hooked it up to the 700W FSP Hydro PSU in my Ryzen 5600X system and it works just fine there.

How much current does the McCake draw and which lane does it use? 5V I presume? I guess 250W PSUs don't cut it? I can swear it used to work fine though...

appiah4 wrote on 2024-12-14, 18:59:

Reseating did not help. It works on my older PSUs when nothing else is attached but gives a voltage error as soon as a hard drive or optical is added. I hooked it up to the 700W FSP Hydro PSU in my Ryzen 5600X system and it works just fine there.

How much current does the McCake draw and which lane does it use? 5V I presume? I guess 250W PSUs don't cut it? I can swear it used to work fine though...

The CM4 uses 5V as the input, and base is around 7W. I'm not sure what it needs under full load with MT32 Pi running.

Did you recently update the software? You can disable the low voltage warning and throttling in the config.txt file on a Pi3. I'm not sure if you can with the CM4, and I'm too lazy to take apart the system to get at my McCake to check myself. So this could have reverted.

It's also possible your PSU started degrading, if you don't need -5V for a soundcard. Running a newer 400-500W ATX PSU with an AT adapter is my go to. The risk of damaging something greatly out weighs any feeling of needing to a power source from the era of the rest of the components.

On cheaper PSUs, sometimes it works when connected to the first molex on a chain but not on the second or third (regardless of whether the others are used or not). On some PSUs it just doesn't work. I find it hard to believe that the PSU is struggling to provide 2A on the 5V lane, but it is what it is. Time to buy a reliable and new PSU for my test bench I guess.

Hello.

I bought the WP32 McCake. If I want to use a Rotary Encoder on the McCake instead of the 2 volume buttons, then the PINs for button 3/4 correspond to CLK/DT on the encoder?!
There is also an ENC PIN on the board. What function does it have?!
Thanks for the help.

Is it possible to access MPU-401 intelligent mode through the wavetable header if the card it is attached to supports intelligent mode, such as a PCMIDI?

Paralel wrote on 2025-03-13, 21:14:

Is it possible to access MPU-401 intelligent mode through the wavetable header if the card it is attached to supports intelligent mode, such as a PCMIDI?

Intelligent mode MIDI just sends data over the regular signal lines. There no additional inputs needed.

I've played intelligent mode required games with this attached to a PicoGUS which does intelligent mode, as well as both a SB16 and YMF719 using SoftMPU.

Paralel wrote on 2025-03-13, 21:14:

Is it possible to access MPU-401 intelligent mode through the wavetable header if the card it is attached to supports intelligent mode, such as a PCMIDI?

Intelligent mode games will just work if you use a PCMIDI card

HI, is there any chance to set startup volume to something lower ?
I find default 100 is overwhelming with distortions for example in Doom1 startup midi.
I know about UNISOUND /VFxx but any other variants, except every next time open case and click volume knob ?

Hey guys ... I purchased a WP32 McCake a long time ago but never used it.

However, I'm now trying to set it up but I only see a black screen on the LCD.

I formatted an SD card as FAT32 and unzipped the files from https://serdaco.com/downloads/WP32McCake/ onto it.

Am I doing something wrong?

All of the lights on the WP32 McCake are illuminated (5V, 3.3V DAC, 3.3V PI, nPWR, Pi ACT, and GPIO.

sofakng wrote on 2025-11-28, 21:38:

Hey guys ... I purchased a WP32 McCake a long time ago but never used it. […]
Show full quote

Hey guys ... I purchased a WP32 McCake a long time ago but never used it.

However, I'm now trying to set it up but I only see a black screen on the LCD.

I formatted an SD card as FAT32 and unzipped the files from https://serdaco.com/downloads/WP32McCake/ onto it.

Am I doing something wrong?

All of the lights on the WP32 McCake are illuminated (5V, 3.3V DAC, 3.3V PI, nPWR, Pi ACT, and GPIO.

You first extracted the zip file to the root of the MicroSD card and then overwrote mt32-pi.cfg with the file outside the zip?

You also need the copywritten MT-32 ROMs which aren't included if you didn't copy those over yet. Even if the screen isn't configured correctly so it's not working, it should still be booting correctly. Try playing MIDI and see if the activity light flashes and if you get any audio out of it.

Is there a way to change the text that appears when switching between MT-32 roms into something more readable?

E.g.

ver1.07 10 oct, 87
mt-32 v2.07 90-05-23
cm32/lapc1.02 891205

to

MT-32 Old
MT-32 New
CM-32/LAPC

I tried changing each of the above using a hex editor, but doing so causes the Mccake to stop detecting the rom.

If you've edited the contents of the MT-32 ROMs themselves, it will have changed their checksums, so MT32Pi is probably rejecting them as invalid.

In theory, it's fixable: there's (probably) going to be a checksum byte somewhere in each ROM that you'd need to adjust so the checksum calculation comes out right.
If you've seen Bits und Bytes recent video(s) on editing the S3 Virge BIOS to fix the black levels being wrong, it's basically the same process he goes through so the card doesn't reject his edited BIOS ROM.

I had a bit of a dive into the MT32-Pi and MUNT codebase

MUNT has a set of hard coded SHA1 values for known good ROM images, so changing anything in the file will basically invalidate it. MT32-Pi is coded to retrieve the info directly from the ROM via MUNT with no options otherwise. So out of the box, there is no way to get it to show anything other than the ROM version string of a known good ROM.

You would need to compile your own MT32-Pi version which updates the CMT32Synth::ReportStatus() function in src/synth/mt32synth.cpp(176) to convert the selected ROM type to a readable string and send that to the display instead of the ROM version.

As a hack you could search for the hard coded SHA1 value of the ROMs you are using inside the compiled binary and replace it with the SHA1 of your modified version, I don't know if that will have any downstream effects.

I love that we're collectively smart enough to know stuff like this, from reverse engineering the bajeezus out of whatever we want to use or can't use anymore. This is what personal computing is REALLY all about.

Thank-you for the responses.

Yep, you are correct, the rom SHA1 strings are hardcoded in MUNT.

ROMInfo.cpp

1static const ROMInfoLists &getROMInfoLists() {
2	static const File::SHA1Digest CTRL_MT32_V1_04_A_SHA1 = "9cd4858014c4e8a9dff96053f784bfaac1092a2e";
3	static const File::SHA1Digest CTRL_MT32_V1_04_B_SHA1 = "fe8db469b5bfeb37edb269fd47e3ce6d91014652";
4	static const File::SHA1Digest CTRL_MT32_V1_04_SHA1 = "5a5cb5a77d7d55ee69657c2f870416daed52dea7";
5...

I'm going to try editing these from the compiled binaries as @NeoG_ suggested.

Problem is I'm pretty sure these binaries are inside the .img files which are ext4 and aren't compatible with Windows.

Need to figure out a way to get access.

If I configure WiFi and FTP using mt32-pi.cfg, will that get me into the Pi's filesystem? Or just the SD card config files and soundfont folder?

EDIT: Ahh dang, it looks like the RPi that came from Serda's shop doesn't have the WiFi module. Other than installing Linux on my machine, does anyone have ideas for accessing the .img files?