These Game Boy test roms were written to complement other test suites. I use them to test my Game Boy emulator AGE for regressions.
All tests are named to include the devices they have been verified to be compatible to.
| Test name | compatible devices | 
|---|---|
| foo-cgbBE.gb | CPU-CGB-B&CPU-CGB-E | 
| foo-dmgC-cgbB.gb | CPU-DMG-C&CPU-CGB-B | 
| foo-ncmBE.gb | CPU-CGB-B (non-CGB mode)&CPU-CGB-E (non-CGB mode) | 
To be able to verify the result of screenshot based tests your emulator should calculate RGB values as follows:
- the four DMG shades are #000000,#555555,#AAAAAAand#FFFFFF
- each CGB 5 bit RGB channel is converted to 8 bits
using the formula (X << 3) | (X >> 2)
- the shades for non-CGB mode are:
- background: #000000,#0063C6,#7BFF31and#FFFFFF
- objects: #000000,#943939,#FF8484and#FFFFFF
 
- background: 
AGE test roms use the Cellphone Font created by domsson.
You need RGBDS to make these roms.
In my experience Visual Studio Code with the RGBDS GBZ80 plugin installed is your best choice.