| | Atlantis (Barcrest) (DAT, Dutch) (MPU4) | 1969 | Barcrest | m4atlan | | 0.00 |
| | Atlantis (LTD) | 1969 | LTD | atla_ltd | | 0.00 |
| | Atleta | 1991 | Inder | atleta | | 0.00 |
| | Atlus PSX | 1996 | Atlus | atluspsx | BIOS | 4.08 |
 | Atomic Boy (revision A) (clone of: wilytowr) | 1985 | Irem (Memetron license) | atomboya | | 0.00 |
| Atomic Boy (revision B) (clone of: wilytowr) | 1985 | Irem (Memetron license) | atomboy | Platform / Run Jump Scrolling | 0.00 |
 | Atomic Point (Korea) | 1990 | Philko | atomicp | Puzzle / Drop | 6.00 |
 | Atomic Punk (US) (clone of: dynablst) | 1991 | Irem America (licensed from Hudson Soft) | atompunk | Maze | 0.00 |
 | Atomic Robo-kid | 1988 | UPL | robokid | Shooter / Flying Horizontal | 6.67 |
| Atomic Robo-kid (Japan, set 1) (clone of: robokid) | 1988 | UPL | robokidj | Shooter / Flying Horizontal | 0.00 |
| Atomic Robo-kid (Japan, set 2) (clone of: robokid) | 1988 | UPL | robokidj2 | | 0.00 |
| | Atomiswave Bios | 2001 | Sammy | awbios | | 7.90 |
| | Atronic SetUp/Clear Chips (Russia, set 1) | 1999 | Atronic | atronic | | 10.00 |
| | Atronic SetUp/Clear Chips (Russia, set 2) (clone of: atronic) | 1999 | Atronic | atronica | | 0.00 |
| | Attack | 1980 | Playmatic | attack | | 0.00 |
| | Attack From Mars (1.0) (clone of: afm_113) | 1995 | Bally | afm_10 | | 0.00 |
| | Attack From Mars (1.1 Ultrapin) (clone of: afm_113) | 1995 | Bally | afm_11u | | 0.00 |
| | Attack From Mars (1.1) (clone of: afm_113) | 1995 | Bally | afm_11 | | 0.00 |
| | Attack From Mars (1.13) | 1995 | Bally | afm_113 | | 0.00 |
| | Attack From Mars (1.13b) (clone of: afm_113) | 1995 | Bally | afm_113b | | 0.00 |
