Last year, I got gifted the legendary Game Boy (shoutout to my German bois), in a let’s say, much more modern variant! Let me walk you through the pain of setting up this little bugger, luckily I’ve had documented my pain in short bullet points.

GPi Case 2 for CM4

Raspberry Pi Compute Module 4

The Goal

Starting point is a beautiful Retroflag GPi Case 2 + Compute Module 4 + 64GB SD card. The goal is to assemble everything, install Recalbox, install some games and play!

Let’s start

  • Found a tutorial how to set it up, looks easy, following the tutorial
  • Got the Raspberry Pi Imager, installed Recalbox on the SD card, easy
  • Downloaded the GPi Case 2 patch, installed it (that patch allows you to use the built-in screen instead of HDMI)
  • The Youtube comments are a bit confusing, some say you don’t need the patch, what is it? (Spoiler: not needed)
  • Put in the SD card, not that easy, it can move slightly
  • Put in the CM4, difficult?? It took a bit until I had it in place, without it falling out… because no screws are needed, you just plug it in, but there is not much space for your fingers :S
  • Started it, it’s on, but nothing is happening, black screen
  • Tried again with a HDMI cable instead, bootloader is trying to boot, looks like the logs are repeating, it’s stuck bro
  • Apparently there is nothing to start, because “no sd card detected”
  • WHYYY ??? Is the SD card properly in place? It was a bit wobbly? I checked - all good. Is it broken? Can’t be, Windows can read from it and write to it, no issues. Maybe the slot is broken?

Of course it’s not working

  • Gooooooogle time, again, yay
  • Turns out there are many different variations of the Compute Module 4
  • Long story short, the light version version can only use the SD card, which I don’t have. I have the CM4 8GB RAM with 32GB storage (eMMC)
  • Why is the YT video not mentioning which variant it uses?? Am I the only fool who has run into this??
  • Let’s continue, the new goal is to flash Recalbox onto the chip
  • Found instructions of how to flash the eMMC
  • Installed rpiboot, took a while until I had figured out the right parameters and how to mount the chip as USB
  • As admin run ./rpiboot.exe -v [-d path to mass-gadget-64 etc.]
  • Plug in the micro USB-B cable and connect with laptop, start the thing and rpiboot will do the magic
  • Now File Explorer shows an unknown/empty volume D, which means I can use the Raspi Imager to install Recalbox again, noice
  • 5 hours later *in French accent*

5 hours later

  • At the end when it verifies the image, it fails with “SD Card broken bla bla blaa”
  • Nooooooooooo

noooooooooo

  • So basically it’s saying, the onboard storage (eMMC) is broken, have I broken the chip while I was trying to place it inside the case?? Somehow I don’t believe it
  • Played around with PARTDISK, cleaning, formatting, creating new partitions bla bla
  • Managed to create a working volume that I can access with the File Explorer
  • Tried to install Recalbox again with the Raspi Imager -> same error at the end
  • After a lot of googling and frustration I got an idea, I just force the image on the chip ( ͡° ͜ʖ ͡°)
  • Downloaded the latest Recalbox image manually, and called in Rufus, let’s go!!
  • Installed the image with Rufus
  • That seemed to work quite well, after 2 minutes it was already installed, almost… *sigh* it’s stuck at 99.9%
  • I cancelled after a while, as nothing was happening - mission failed - again
  • Regardless, tried to boot up the module -> black screen
  • Again with HDMI, I cannot believe it… Recalbox is starting up
  • I just cannot use any buttons to control it
  • Plugged in my Microsoft controller -> doesn’t work
  • Great, I have bruteforced the Recalbox image onto the chip, but I cannot use it… :S

Did you really think it would be that easy?

  • Let’s mount the eMMC chip again and see what else I can do
  • Windows (or is it rpiboot??) has problems to mount the chip as volume, so I can’t really access it, I also can’t install anything else on it, since I need an accessible volume
  • Shite.. I might haved bricked the whole thing :cry:
  • Let’s try the same bullshit again, just from a Linux machine
  • I just needed to mount it manually and repeat the whole process
  • Recalbox is installed yet again :cool:
  • But I need to install the patch, which is a batch file, only used by Windows :S (or do I?)
  • Tried starting without patch, as I use the HDMI anyway, well it’s starting up but I STILL DONT HAVE ANY CONTROLS (I’m going crazy)
  • Let’s try on Windows again, after several attempts mounting the chip with rpiboot (which sometimes randomly doesn’t work?), I gained access
  • I finally have access to the chip again, and could install some roms, *wohooo*, but before I can do anything with it I need to make the system usable
  • Installed patch
  • Started without HDMI, black screen
  • Started with HDMI, black screen
  • Uninstalled patch
  • Started with HDMI, it WORKS!!
  • Alright, I need to make the controls somehow work, let’s get a terminal and see what we can do
  • Plugged in a keyboard, tried to open a terminal with some shortcuts, that should work according to Recalbox docs, but only a Recalbox-screen pops up, no terminal in sight

What a journey, like a rollercoaster lol, but I’m making slowly progress! Up until here (16.12.2024) I have spend many hours troubleshooting and jumping from one issue to the next one. So far, we have installed Recalbox, it’s booting, but controls are missing. Next mission: get access to the terminal, I guess?

Back into the last round

It’s January 2025, after a litte christmas break I’m back from Germany and ready to continue with the fun. I didn’t manage to get acccess to the terminal, nor did anything else work, so what do we do if nothing works? Yeah let’s just try again :)

  • Run Git Bash as admin (yes I need my linux commands even on Windows)
  • cd C:\Apps\ Raspberry Pi and ./rpiboot.exe -v
    • without -d /path/to/massgadget/ as it would only mount the volume SHARE!
  • Now we have mounted REACALBOX (D:\) and SHARE (E:\)
  • Run Raspi Imager (v1.8.5)
    • Select “Raspi 4 / CM4 / bla bla”
    • Select Recalbox as OS
    • Select the mounted eMMC (RPi-MSD-0001)
  • The image version is Recalbox 9.2.3-Pulstar 64bits for Raspi 4 / 400 / CM4 / GPiCase2 / PiBoyDMG (released 2024-08-01)
  • Started the device with HDMI -> it WORKS
  • Started the device without HDMI -> it WORKS
  • Niccce

niceee

It’s working

At this point I don’t even know what exactly has worked and what not? I might find out whenever I’m brave enough to reinstall everything, but for now, I will only put some more games on it and play! If this finds you, may you have an easier journey than me lol.

What have I learned?

One word, patience.



Resources

Additional resources that I have used to troubleshoot

Wireless RAM Storage SKU Part # EAN
YES 8GB 32GB SC0678 CM4108032 0617588405464