start:
mov cmod,#00h
mov ch,#00h
mov cl,#00h
mov ccapm0,#21h
setb ec
setb cr
jnb testflag1,$




pca_interrupt:
clr ccf0
jb flagrpm,second_capture
first_capture:
mov captureL,ccap0l
mov captureH,ccap0h
mov ccapm0,#21h
setb flagrpm
reti
second_capture:
clr c
mov a,ccap0l
subb a,captureL
mov rpm_captureL,a
mov a,ccap0h
subb a,captureH
mov rpm_captureH,a
setb testflag1
reti