frequency and duty cycle??

what is and how do i obtain the frequency and duty cycle of the sqaure wave generated by the following code?

MOV TMOD,#2H MOV TH0,#-250 AGAIN: SETB P1.4 ACALL DELAY CLR P1.4 ACALL DELAY SJMP AGAIN DELAY: SETB TR0 BACK: JNB TF0,BACK CLR TR0 CLR TF0

check this out http://tscm.com/dutycy.pdf sorry i cant help more

Easiest way is to look at it with an oscilloscope www.dpscope.com

what is and how do i obtain the frequency and duty cycle of the sqaure wave generated by the following code?

Without knowing the clock speed, impossible to say.
Maybe ask in an 8051 forum? :wink:

[edit]FWIW, my guess* is that the duty cycle is 50%

*Caveat: I haven’t used an 8051 in the last quarter century
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