Retro Arcade featuring Pac-Man
Needs better images.
The Pac-Man Plug & Play is pretty much Namco Museum...on a Plug & Play!
On the opening screen, hold Up and press A, then release Up and press Down to enter Debug Mode.
ROM Checksum Soak Mode
A ROM checksum mode left behind by the developers.
Hardware Test Mode
A hardware test for the controller. There are also graphics and sound effects from Ms. Pac Man present on the menu.
Save Data Test
A fake data save test.
Color Test Mode
A color test for the TV.
Music Test Mode
A music/sound test from all games. Interestingly, the menu includes two unused games, Ms. Pac-Man and Jr. Pac-Man. Ms. Pac-Man appears in every Pac-Man Plug & Play test mode (even if the game isn't included on the console), but Jr. Pac-Man is brand-new. Presumably neither game was included due to the ridiculous copyright issues that arose with them right before this system's release. Dig Dug's music and sound effects seem to be different from the game.
Dig Dug music test sounds
Game Color Test
A game color test that contains the ghosts from Pac-Man. They have colors that fade away. If you keep pressing A the colors will change to green, yellow, blue, magenta, and cyan, respectively.
Sleep Mode Test
A sleep mode test that uses music from New Rally-X. There's an option to turn the Menu button's LED on and off.