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???
02/18/03 21:46
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 		 #39389 - RE: calculating a delay ms and us
Responding to: ???'s previous message
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void 2usdelay(unsigned char d) 
{ unsigned char i; 
for(i=0;i<d;d++) 
}

will still give 3-5 instruction cycles per d value depending on the compiler (version).

the only way to get it right is:

for 12 MHz clock (you should use 11.0592 instead and adjust the constant 247)
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Delay500us:             ;call = 2 cycles
       mov  r0,#247     ; 1 cycle
       djnz r0,$        ; 2* 247 cycles
       nop              ; 1 cycl2
       ret              ; 2 cycles
;      total             500 cycles


Erik

List of 10 messages in thread
TopicAuthorDate
calculating a delay ms and us            01/01/70 00:00      
   RE: calculating a delay ms and us            01/01/70 00:00      
      RE: calculating a delay ms and us            01/01/70 00:00      
         RE: calculating a delay ms and us            01/01/70 00:00      
         RE: calculating a delay ms and us            01/01/70 00:00      
            RE: calculating a delay ms and us            01/01/70 00:00      
         RE: calculating a delay ms and us            01/01/70 00:00      
            RE: calculating a delay ms and us            01/01/70 00:00      
   RE: calculating a delay ... addendum            01/01/70 00:00      
      RE: calculating a delay ... addendum            01/01/70 00:00      

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