; Reusable NES hardware symbols only
PPUCTRL=$2000
PPUMASK=$2001
PPUSTATUS=$2002
OAMADDR=$2003
OAMDATA=$2004
PPUSCROLL=$2005
PPUADDR=$2006
PPUDATA=$2007
SQ1_VOL=$4000
SQ1_SWEEP=$4001
SQ1_LO=$4002
SQ1_HI=$4003
SQ2_VOL=$4004
SQ2_SWEEP=$4005
SQ2_LO=$4006
SQ2_HI=$4007
TRI_LINEAR=$4008
TRI_LO=$400A
TRI_HI=$400B
NOISE_VOL=$400C
NOISE_LO=$400E
NOISE_HI=$400F
DMC_FREQ=$4010
DMC_RAW=$4011
DMC_START=$4012
DMC_LEN=$4013
OAMDMA=$4014
SND_CHN=$4015
JOY1=$4016
JOY2=$4017