The Rev 1 ROM carries the header the disassembly writes, and its bytes sum to the global checksum the disassembly gives, $16BF. | 0x14C-0x14F | Verified |
| Pressing Left or Right moves the piece at once and sets a counter to 23; each held frame counts it down, and at 0 the piece moves and the counter restarts at 9, so a held piece moves again 23 frames after the press and then every 9. | 0x2509-0x2572 | Verified |
| Gravity reloads a countdown from a table of 21 values, one per level index from 52 at index 0 down to 2 at index 20, and the piece falls a row when the countdown passes 0, so it falls every 53 frames at index 0 and every 3 at index 20. | 0x1AE8-0x1B1A | Verified |
To pick a piece, the game reads the hardware divider DIV, reduces it modulo 7, and checks the result against the piece now spawning and the one after it; it reads again when the three type ids OR together to the spawning piece's, and takes the third read regardless. | 0x2007-0x2070 | Code |
| In 9,000 pieces dealt over 474 games on the original Game Boy, L came 10.84% of the time and O 16.74%, and 11.55% of pieces repeated the one before. | 0x2007-0x2070 | Verified |