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<span style="font-size:200%;">[[Mappers]]</span> | |||
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=== [http://bootgod.dyndns.org:7777/stats.php?page=6 Top 10 mappers used (NesCartDB)] === | |||
{| class="wikitable" style="text-align: center" | |||
! by usage | |||
|- | |||
|{{mapper|001|i}} <br /> {{mapper|004|i}} <br /> {{mapper|002|i}} <br /> {{mapper|000|i}} <br /> {{mapper|003|i}} <br /> {{mapper|007|i}} <br /> {{mapper|206|i}} <br /> {{mapper|011|i}} <br /> {{mapper|005|i}} <br /> {{mapper|019|i}} <br /> | |||
|- | |||
! ascending | |||
|- | |||
|{{mapper|000|i}} <br /> {{mapper|001|i}} <br /> {{mapper|002|i}} <br /> {{mapper|003|i}} <br /> {{mapper|004|i}} <br /> {{mapper|005|i}} <br /> {{mapper|007|i}} <br /> {{mapper|011|i}} <br /> {{mapper|019|i}} <br /> {{mapper|206|i}} <br /> | |||
|} | |||
== Mapper ideas == | == Mapper ideas == | ||
Latest revision as of 16:38, 3 November 2016
Top 10 mappers used (NesCartDB)
| by usage |
|---|
 001 004 002 000 003  007  206  011 005 019 |
| ascending |
| 000 001 002 003 004 005 007 011 019 206 |
Mapper ideas
- CHR hardware scrolling unit
- Scrolls portions of pattern table with wrapping for hardware accelerated parallax effects
- implementation: two CHR ROMs with alternately stored tiles (VRAM address %0AAAAA AAAcBBBB -> ROM %c, address in ROM %AAAAAAAABBBB) for parallel fetching of pixel rows
- Scrolls portions of pattern table with wrapping for hardware accelerated parallax effects
- CHR color remapping unit
- ExGraphix-like, with each byte in ExRAM storing a color index (0-3) to be remapped to in a character, for every source color index (0-3). This would allow to conserve some palette/CHR-ROM space in some cases.
Example:
- ExGraphix-like, with each byte in ExRAM storing a color index (0-3) to be remapped to in a character, for every source color index (0-3). This would allow to conserve some palette/CHR-ROM space in some cases.
ExRAM byte = %01010000, or 1100 in quaternary system: remap 0 to 0, 1 to 0, 2 to 1, 3 to 1
Original character:
.defchr $00000000,
$02233200,
$02100120,
$03000030,
$03333310,
$03000030,
$03000030,
$03222210
Remapped:
.defchr $00000000,
$01111100,
$01000010,
$01000010,
$01111100,
$01000010,
$01000010,
$01111100
- DPCM converter
- Converts any on-cartridge audio to DPCM and returns it to CPU on sample reads so that there's audio expansion on NES!
- DMC rate control would coarsely alter pitch if the conversion rate is constant
- Converts any on-cartridge audio to DPCM and returns it to CPU on sample reads so that there's audio expansion on NES!
- DPCM hardware mixer
- Plays back (by returning to CPU on sample read) multiple samples at different speeds
