1)for reloading timer and maintain high stability of timer tick its good
to disable interrupts when reload TL,TH . But:
- make EA=1 right after TL,TH loading
- do not overwrite TL,TH , make someting like this
timer1reload:
mov a,#246 ; ;timerl
mov r3,#216 ;timerh
clr EA
clr TR1
add a,TL1 ;
mov TL1,a ;
mov a,TH1 ;
addc a,r3 ;
mov TH1,a ;
setb TR1 ;
setb EA
ret
2)For serial receiver (and at 2400 baud) its not naccassary to clear EA.
regards