PiEmuCD is a Python script that uses the Linux USB Gadget kernel modules to turn your Raspberry Pi Zero (W) into one or more emulated USB CD-ROM drives.

Documentation is a work in progress.

1. Prepare the SD Card

• Flash Raspberry Pi OS Lite (Bullseye) to an SD Card (16 GB minimum recommended size)
  • Use the Pi Imager tool to preconfigure hostname, login and locale
• Use a partitioning tool to:
  • Extend system partition to 4 GiB
  • Create new partition, exFAT for the rest of the SD card -> this partition is called the image store.
• Edit files from boot partition
  • Add dtoverlay=dwc2 to config.txt
  • From cmdline.txt emove quiet and init=/usr/lib/raspberrypi-sys-mods/firstboot to prevent the OS from resizing the root partition on first boot

2. Configure the Raspberry Pi

• Connect to the Pi, either via HDMI + keyboard, SSH or Serial
• Copy the piemucd.py to the home folder of your user
• Add sudo python3 ~/piemucd.py to the end of ~/.profile to have the script start up on login
• Set up the user to automatically login on startup using sudo raspi-config

3. Main interface

• When PiEmuCD is run, it automatically starts up in CD emulation mode. If no to-be-mounted.txt file is present on the root of the image store partition, the operation will fail.
• PiEmuCD has it's own command interface with few commands supported. Type help to get a list of all available commands.
• switch will switch modes, switch cdrom will switch to CD-ROM emulation mode and switch store will switch to the image store being mounted on the virtual USB drive.

4. "To be mounted" file

• The to-be-mounted.txt file specified which of the images on the image store should be mounted in CD-ROM emulation mode.
• A sample file is provided in the repository.