• 8-bit for delay and sound
• stored as registers
• value goes from 0 to 60
• if value > 0, then decrement by one 60 times a second
• independent of emulator loop
• sound timer → beeps as long as above 0
• emulator runs normally while timer decrements
  • game will check the value and delay if needed
• core design problems:
  • because they need to be “independent” from the emulator loop BUT don’t really use a separate thread (for simplicity + race conditions might arise)
  • the native machine might not also operate at 60Hz
  • resolution:
    • we directly track when at least 1 “tick” (i.e. $\frac{1}{60}$ of a second) occurs (by fetching the elapsed timing)
    • if a tick does occur, we decrement the timers by that number of ticks
• requires some tweaking to work