一种基于avr的多任务机制

reti
;----------------------*
; pc=0xA3(0x146)
;
L00A3:
rcall L006D
in r2,p3D
in r3,p3E
sts D0061,r3
sts D0060,r2
movw r16,r2
rcall L0068
sei
clr r2
out p18,r2
rjmp L00C7
; ----------- jump on last line
L00B0:
lds r20,D0064
clr r21
cpi r20,k01
ldi r30,k00
cpc r21,r30
breq L00C0
; ----- branch on last line
cpi r20,k02
ldi r30,k00
cpc r21,r30
breq L00C2
; ----- branch on last line
cpi r20,k03
ldi r30,k00
cpc r21,r30
breq L00C4
; ----- branch on last line
rjmp L00C6
; ----------- jump on last line
L00C0:
rcall L0054
rjmp L00C7
; ----------- jump on last line
L00C2:
rcall L0059
rjmp L00C7
; ----------- jump on last line
L00C4:
rcall L005E
rjmp L00C7
; ----------- jump on last line
L00C6:
rcall L0063
L00C7:
rjmp L00B0
; ----------- jump on last line
ret
;----------------------*
; pc=0xC9(0x192)
;
__text_end::
;
; last flash byte address = 0x0191
; last flash word address = 0x00C8
;---------------------------------------
.area bss (abs)
.org 0x0060
;
__first_bss::
;
D0060:
.blkb 1
D0061:
.blkb 3
D0064:
;
__last_bss::
;
; last lds/sts data byte at 0x0064
;---------------------------------------
;