User:Dr. Floppy/Apex
Apex is a side-scrolling adventure/exploration game. It serves as a testament to the "golden age" of console gaming (circa early '90's)- a celebration of what was, what is and what might have been.
Overview
- Project Owner: Retrometheus
- Developer: Retrometheus
- Compiler: None (hex coding)
- Sound Driver: Retrodriver™
- Soundtrack by: Retrometheus
- Started on: 5/2011
- Status: Preproduction
- Mapper: MMC5 (unique submapper, tentatively dubbed "EJROM")
- PRG-ROM: 1024 KB
- CHR-ROM: 1024 KB
- PRG-RAM: 64 KB
Story
Bioterrorists are cultivating superviruses in labs hidden at the bottom of the ocean.
Gameplay
Apex is a rather nondescript purple angelfish with two basic attacks: a stationary somersault and high-velocity bubble projectiles.
RAM Map
| RAM | Function | Details |
| 0x0000-0D | Music Channel pointers | P2-P1-T-N-D-P3-P5 |
| 0x000E-0F | Rhythm Array pointer | |
| 0x0010-1D | Repeat Coda pointers | P2-P1-T-N-D-P3-P5 |
| 0x001E | Song Data bank# | |
| 0x001F | DPCM sample data Bank# | |
| 0x0020-2C | Rhythmic countdowns (even slots only) | P2-P1-T-N-D-P3-P5 |
| 0x0021-2D | Selective repeats # remaining (odd slots only) | P2-P1-T-N-D-P3-P5 |
| 0x002E-2F | Header pointer | |
| 0x0030-32 | Timbre/volume data | P2-P1-T |
| 0x0033 | Song ID# jukebox | Writing a value here triggers a new song to play. |
| 0x0034 | Current song ID# | |
| 0x0035-36 | Timbre/volume data | P3-P5 |
| 0x0037 | Reserved for SFX. | |
| 0x0038-3E | Most recent rhythmic countdown value | Used to reload even-numbered slots in the $20-2C range. |
| 0x003F | Reserved for SFX. | |
| 0x0040-5B | Unused | |
| 0x005C | Current macromode | |
| 0x005D | Macromode transition destination | |
| 0x005E | Reserved | |
| 0x005F | Transition status | #00 = Null; #01 = Activate; #FF = Transitioning |
| 0x0060-AF | Unused | |
| 0x00B0-B2 | Controller 1 buttons | old-regular-new |
| 0x00B3-B7 | Reserved | |
| 0x00B8-BA | Controller 2 buttons | old-regular-new |
| 0x00BB-BF | Reserved | |
| 0x00C0 | Current spritesheet | |
| 0x00C1 | Current BG tilesheet | |
| 0x00C2-DF | Unused? | |
| 0x00E0 | Game Paused? | #00 = No; #01 = Yes |
| 0x00E1-F7 | Unused? | |
| 0x00F8 | SPR-OAM transfer on next NMI? | #00 = yes |
| 0x00FC | Frame counter | See what we did there? |
| 0x00FF | Used in terminal MPL loop | |
| 0x0100-1FF | Stack | |
| 0x0200-2FF | Sprites |
ROM Map
$00010-0400F: Default music data bank
$04010-1000F: Alternate music data banks
$E0010-F000F: PRG-RAM banks (8 x 8 kB)
$F0010-FE00F: Seven 8kB DPCM banks
$FE010: NMI Routine
$FF010: Init. Routine
$FF090: Title Screen draw routine
$FF0F0-FF10F: Title Screen palettes
$FF210: Main Program Loop
$FFC10: Music frequency table
$FFD10: Tempo Offsets
$FFF10: Music/Tempo/DPCM Bank index
$100000: Waiting for NMI
