mirror of
https://github.com/fadden/6502bench.git
synced 2024-11-13 13:10:51 +00:00
b4519b2aa2
The PPU registers are mirrored from $2000-3FFF.
54 lines
2.0 KiB
Plaintext
54 lines
2.0 KiB
Plaintext
; Copyright 2018 faddenSoft. All Rights Reserved.
|
|
; See the LICENSE.txt file for distribution terms (Apache 2.0).
|
|
;
|
|
; Adapted from various online references, notably https://wiki.nesdev.com/
|
|
|
|
*SYNOPSIS Nintendo Entertainment System registers
|
|
|
|
; PPU registers ($2000-2007, repeating every 8 bytes to $3FFF)
|
|
; (see https://wiki.nesdev.com/w/index.php/PPU_registers)
|
|
;
|
|
; pattern: 001? ???? ???? ?xxx
|
|
*MULTI_MASK %0010000000000000 %0010000000000000 %0000000000000111
|
|
|
|
PPUCTRL @ $2000 ;W VPHB SINN various
|
|
PPUMASK @ $2001 ;W BGRs bMmG various
|
|
PPUSTATUS @ $2002 ;R VSO- ---- various; read resets $2005/2006
|
|
OAMADDR @ $2003 ;W OAM read/write address
|
|
OAMDATA @ $2004 ;RW OAM data read/write
|
|
PPUSCROLL @ $2005 ;WW fine scroll position (two writes: X,Y)
|
|
PPUADDR @ $2006 ;WW PPU read/write address (two writes: MSB, LSB)
|
|
PPUDATA @ $2007 ;RW PPU data read/write
|
|
|
|
*MULTI_MASK
|
|
|
|
; APU and I/O registers
|
|
; (see https://wiki.nesdev.com/w/index.php/2A03)
|
|
SQ1_VOL @ $4000 ;DDLC VVVV
|
|
SQ1_SWEEP @ $4001 ;EPPP NSSS
|
|
SQ1_LO @ $4002 ;TTTT TTTT
|
|
SQ1_HI @ $4003 ;LLLL LTTT
|
|
SQ2_VOL @ $4004 ;DDLC VVVV
|
|
SQ2_SWEEP @ $4005 ;EPPP NSSS
|
|
SQ2_LO @ $4006 ;TTTT TTTT
|
|
SQ2_HI @ $4007 ;LLLL LTTT
|
|
TRI_LINEAR @ $4008 ;CRRR RRRR
|
|
TRI_UNU @ $4009
|
|
TRI_LO @ $400a ;TTTT TTTT
|
|
TRI_HI @ $400b ;LLLL LTTT
|
|
NOISE_VOL @ $400c ;--LC VVVV
|
|
NOISE_UNU @ $400d
|
|
NOISE_LO @ $400e ;L--- PPPP
|
|
NOISE_HI @ $400f ;LLLL L---
|
|
DMC_FREQ @ $4010 ;IL-- RRRR
|
|
DMC_RAW @ $4011 ;-DDD DDDD
|
|
DMC_START @ $4012 ;AAAA AAAA
|
|
DMC_LEN @ $4013 ;LLLL LLLL
|
|
OAMDMA @ $4014 ;AAAA AAAA OAM DMA high address
|
|
SND_CHN @ $4015 ;W:---D NT21 R:IF-D NT21
|
|
JOY1 @ $4016 ;joystick 1 data (R) and joystick strobe (W)
|
|
JOY2 @ $4017 ;joystick 2 data (R) and frame counter (W)
|
|
|
|
; $4018-401F normally disabled, but used in test mode
|
|
; (see http://wiki.nesdev.com/w/index.php/CPU_Test_Mode)
|