witch sound tracker

inspired by lsdj, but couldn't hold a candle to it. I made this rare ROM that modifield sound register directly, same that lsdj can navegate using joypad convinations 

use SELECT+DPAD to change sound Chanel 

PU1 

NR10 to NR14

PU2

NR21 to NR24

 NOI 

NR41 to NR44

(wav aren't implement)

MIX are mixed registers. 

NR50 to NR52

More detailed here

https://gbdev.gg8.se/wiki/articles/Gameboy_sound_hardware

use A+DPAD to change values

use B to paste current value 

LEN is a total steps duration

DEY is a delay() per step