There are a bunch of test roms (and sample roms) in the repo, but you'll have to edit the Chip8Wrapper file (it's obvious where).
The keypad is currently hardcoded as
1 2 3 4
Q W E R
A S D F
Z X C V
The emulator passes all of the standard 'tests' now, but it fails on the 'oob' out of bounds test rom.
(these items have been re-written as 'issues' in Guthub now)
https://en.wikipedia.org/wiki/CHIP-8
http://devernay.free.fr/hacks/chip8/C8TECH10.HTM
https://github.com/Timendus/chip8-test-suite?tab=readme-ov-file for tests
(but note this errata - https://github.com/gulrak/cadmium/wiki/CTR-Errata )
https://www.laurencescotford.net/2020/07/25/chip-8-on-the-cosmac-vip-index/
https://tobiasvl.github.io/blog/write-a-chip-8-emulator/
https://chip8.gulrak.net/