RetroFlag GPi Case
So I figured out what to do with my Raspberry Pi Zero that I got from issue 40 of the MagPi... Yes, you guessed it, yet another retro game machine. This time a handheld Game Boy inspired case powered by retropie.
The MagPi article on RetroFlag GPi Case has everything you need to know about completing a build with a Raspberry Pi Zero and the RetroFlag GPi Case. I really like the colour IPS screen and authentic look and feel of the case, just like using a real Game Boy.
There are issues with using a Raspberry Pi Zero in that there is no Ethernet port or WiFi to connect to the Pi. I had to use a micro-B USB cable and connect with PuTTY whilst sharing the internet connection from my desktop PC to complete the installation and configuration. The Retroflag GPi Case has safe shutdown and reset scripts that need to be installed to prevent damage to the Pi or SD card if it's switched off improperly. These are easily installed from GitHub with a wget command if there is an internet connection to the Pi. There is also a batch command that needs to be executed on the SD card to configure the screen of the Retroflag GPi Case.
Games can be added to RetroPie easily by transferring ROMs directly to the SD card via a card reader. However, this is nowhere near as simple as it is with my Picade build which simply uses FTP transfers over WiFi.
Keep it fresh!
Raspberry PI Zero is a fully-fledged Raspberry Pi with a 1GHz processor and 512Mb of RAM! So it’s faster than the original Raspberry Pi!
Revisiting the RetroFlag GPi Case
I had to switch the original Pi Zero for a newly acquired Pi Zero W (wireless), I used this Tom's Hardware article to connect with Bonjour (weird) by direct USB connection. I was then able to bridge my wi-fi connection from my computer to the Pi Zero W to run sudo apt update and sudo apt upgrade.
Hopefully, I'll be able to connect over a wireless internet connection to update RetroPie and add more games as I wish.
Check this article if the Pi Zero is recognised as COM3 https://forums.raspberrypi.com/viewtopic.php?t=245184
Revisiting the RetroFlag GPi Case - Take Two
So there were issues with the first attempt, mainly that the Pi Zero W that I got from eBay was faulty and the wireless didn't work!
Anyway post-pandemic and two years later, I've acquired another one from Pimoroni. I've also found out that the SD card had shit the bed, so a new one of those was also required.
For my future sanity, here are some useful steps to install a properly working installation of RetroPie compatible with the GPi case.
Create an image of RetroPie using the latest version of the Raspberry Pi Imager software.
Download GPi case config and overlay files and place into root directory and run GPi_Case_patch\install_patch.bat from within Windows explorer. This is because Retropie and Recalbox systems default display output is HDMI. GPi CASE has to transfer display output to GPIO for it to work correctly. NB - The audio is not set correctly in this config.txt file. See point 6.
Enable ssh by placing a blank text file called 'ssh' on to the root directory, visible with Windows explorer (D:\boot).
Alter wpa_suppplicant.conf file to configure access to the wireless network. The Pi should now be accessible over wifi and can be accessed with PowerShell using the default credentials e.g. 'ssh pi@retropie.local'. If necessary the hostname can be changed to RetroPie_GPi to avoid confusion with the Picade.
Install safe shutdown scripts and make sure the switch is set for this on the back of the GPi case. It may nbe best to use the script below to complete this process;
wget -O - "https://raw.githubusercontent.com/RetroFlag/retroflag-picase/master/install_gpi.sh" | sudo bash
For audio issues, alter config.txt as below. Note commented out lines and new line added.
#dtoverlay=pwm-2chan,pin=18,func=2,pin2=19,func2=2
#dtoverlay=pwm-audio-pi-zero
# do not use pwm-2chan or the pi-zero pwm audio overlay
dtoverlay=audremap,pins_18_19,enable_jack=on,swap_lr
Install WinSCP to transfer files over wifi!
All of the required files can be found on the NAS under 'SD Card Images'.
There is also no need to install and use Bonjour as previous if the wireless connectivity is available.