Skip to content

Instantly share code, notes, and snippets.

@petrihakkinen

petrihakkinen/eric1_halt_cpu

Last active August 29, 2015 14:11
Show Gist options
  • Save petrihakkinen/0a5e26c63f1e6fab65a2 to your computer and use it in GitHub Desktop.
Save petrihakkinen/0a5e26c63f1e6fab65a2 to your computer and use it in GitHub Desktop.
Download ZIP
Raw
eric1_halt_cpu
; halt CPU (20 cycles)
sts TCCR2B, r0 ; TCCR2B = 0
call delay16 ; wait a while so that the 6502 can finish whatever it was doing
cbi _SFR_IO_ADDR(PORTD), BUS_ENABLE ; disable bus
; ATmega can now do whatever dirty tricks it likes in the memory
; restart CPU (5 cycles)
sbi _SFR_IO_ADDR(PORTD), BUS_ENABLE ; enable bus
ldi r24, 1
sts TCCR2B, r24 ; TCCR2B = 1 (prescaler 1 equals 1 MHz)
Sign up for free to join this conversation on GitHub. Already have an account? Sign in to comment