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Add more DMA registers. Add links to docs.

main
Colin McMillen 9 years ago
parent
commit
abd636a93e
  1. 14
      pewpew.asm
  2. 40
      registers.asm

14
pewpew.asm

@ -83,6 +83,18 @@ MainLoop:
LoadPaletteAndTileData:
; For more details on DMA, see:
; http://wiki.superfamicom.org/snes/show/Grog%27s+Guide+to+DMA+and+HDMA+on+the+SNES
; http://wiki.superfamicom.org/snes/show/Making+a+Small+Game+-+Tic-Tac-Toe
;
; A lot of the graphics-related registers are explained in Qwertie's doc:
; http://emu-docs.org/Super%20NES/General/snesdoc.html
; ... but be careful, because there are some errors in this doc.
;
; bazz's tutorial (available from http://wiki.superfamicom.org/snes/) is
; quite helpful with palette / sprites / DMA, especially starting at
; http://wiki.superfamicom.org/snes/show/Working+with+VRAM+-+Loading+the+Palette
; 16-bit X/Y registers. Used for DMA source address & transfer size, both of
; which want 16-bit values.
; TODO(mcmillen): change back to 8-bit when we're done?
@ -379,4 +391,4 @@ FillScratchLoop:
.ORG 0
.SECTION "TileData"
.INCLUDE "tiles.asm"
.ENDS
.ENDS

40
registers.asm

@ -15,6 +15,9 @@
; I've also heavily borrowed from Yoshi's descriptions of what these registers
; do, though in many cases I've clarified / simplified the descriptions based
; on my own understanding, or simply reformatted them a bit.
;
; Here is a link to an online version of Yoshi's doc (v. 2.30):
; http://patpend.net/technical/snes/snes.txt
; $2100: Screen display initialization [INIDISP]
; Format: x000bbbb
@ -155,20 +158,55 @@
; 011 = 2 addresses write twice: LLHH
; 100 = 4 addresses: LHLH
.define DMA0CTRL $4300
.define DMA1CTRL $4310
.define DMA2CTRL $4320
.define DMA3CTRL $4330
.define DMA4CTRL $4340
.define DMA5CTRL $4350
.define DMA6CTRL $4360
.define DMA7CTRL $4370
; $43x1: DMA destination for channel x. [BBADX]
; The upper byte is assumed to be $21, so the possible destinations are
; $2100-$21FF.
.define DMA0DST $4301
.define DMA1DST $4311
.define DMA2DST $4321
.define DMA3DST $4331
.define DMA4DST $4341
.define DMA5DST $4351
.define DMA6DST $4361
.define DMA7DST $4371
; $43x2-$43x3: DMA source address for channel x. 2 bytes. [AITXL/AITXH]
.define DMA0SRC $4302
.define DMA1SRC $4312
.define DMA2SRC $4322
.define DMA3SRC $4332
.define DMA4SRC $4342
.define DMA5SRC $4352
.define DMA6SRC $4362
.define DMA7SRC $4372
; $43x4: DMA source bank for channel x [AIBX]
.define DMA0SRCBANK $4304
.define DMA1SRCBANK $4314
.define DMA2SRCBANK $4324
.define DMA3SRCBANK $4334
.define DMA4SRCBANK $4344
.define DMA5SRCBANK $4354
.define DMA6SRCBANK $4364
.define DMA7SRCBANK $4374
; $43x5: DMA transfer size & HDMA address. 2 bytes. [DASXL/DASXH]
; When using DMA, $43x5 defines the # of bytes to be transferred via DMA
; itself. When using HDMA, $43x5 defines the data address ($43x5 = low byte,
; $43x6 = hi byte).
.define DMA0SIZE $4305
.define DMA0SIZE $4305
.define DMA1SIZE $4315
.define DMA2SIZE $4325
.define DMA3SIZE $4335
.define DMA4SIZE $4345
.define DMA5SIZE $4355
.define DMA6SIZE $4365
.define DMA7SIZE $4375
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