Programming for the Gameboy/Memory and memory-mapped register layout
Special registers ($FF00 - $FF4B )
edit| Address | $FF00
|
| Description | Used to read back the device's button inputs, i.e. if A button is held |
| Bit 0 | P10 in port |
| Bit 1 | P11 in port |
| Bit 2 | P12 in port |
| Bit 3 | P13 in port |
| Bit 4 | P14 out port |
| Bit 5 | P15 out port |
| Bit 6-7 | Unused |