With calculator from the web page..
Set Freq at - 12000000
Set Bus Divide = 12
Set Entry A = 100
Set N constant = 248
Inner Loop NOPs = 2
Outter Loop NOPs = 1
One Time NOPs = 0

You get a total delay of 0.100002 seconds. In other words, configured this way the subroutine is a generic 1 mSec delay routine with the total delay up to 255 mSec specified by the entry A value.


I posted this example particularly so that persons new to 8051 assembly language programming can better see how to interpert the delay loop calculator I have linked on the previous port to this thread.

Michael Karas


Here is what that subroutine would look like:

Delay:
  push   acc
  mov    a,#248
DelayLp:
  nop
  nop
  djnz   acc, DelayLp
  nop
  pop    acc
  djnz   acc, Delay
  ret

This type of subroutine is nice becasue it does not use any registers, will work nicely without regard to register bank settings and can be called only by having to setup one register, namely A.

Michael Karas