labs/lab2/blink.asm

25 lines
780 B
NASM

.include "msp430g2553.inc"
org 0xC000
start:
;mov.w #0x5a80, &WDTCTL
mov.w #WDTPW|WDTHOLD, &WDTCTL
mov.b #0x41, &P1DIR ; #01000001b (P1.6 == LED2, P1.0 == LED1)
mov.w #0x01, r8 ; #00000001b (start on LED1)
repeat:
mov.b r8, &P1OUT
xor.b #0x41, r8 ; #00000001b -> #01000000b -> ... (LED0 -> LED1 -> ...)
mov.w #40000, r9 ; counts to decrement before blink
mov.w #40000, r10 ; counts to decrement (2nd dec, since 16-bit max value is 65536)
waiter1:
dec r9
jnz waiter1 ; r9 not yet 0
waiter2:
dec r10
jnz waiter2 ; r10 not yet 0
jmp repeat ; r9, r10 == 0; blink other LED
org 0xfffe
dw start ; set reset vector to 'init' label