luigi grimaldi wrote:
-------------------------------
is it poss to write a variable length delay using parameter passing (ie registers) in asm, ive come up with this bit of code but something tells me it could be done better, regs set for 5milisecond delay with 12mhz clock, or maybe this is it?

org 0H
mov sp,#5FH
mov tmod,#10H
mov tcon,#00H
mov R0,#0ECH
mov R1,#077H

delay:
mov TH1,R0
mov TL1,R1
setb TR1
loop:
jnb TF1,loop
clr TR1
clr TF1
jmp delay
end


;no need to use r1,r2 as TH1,TL1 can be used to pass delay. you can load them directly like

mov TH1,#high(0ffffh-<delay in us>);
mov TH1,#low(0ffffh-<delay in us>);
call delay


new delay routine will be


delay:
setb TR1
loop: jnb TF1,loop
clr TR1
clr TF1
ret

abhishek