Andrew Capon

56371 - slow GPIO - SoundBite Board

Discussion created by Andrew Capon on Sep 21, 2010
Latest reply on Sep 22, 2010 by Andrew Capon

Hi Guys,

 

I am flipping PF7 from high to low to see what speed I can get with the following code:

 

 

 
 while(1) { __asm("bset #7,y:(%0)" : : "A" (M_PDRF));0x000001fe <FACTest+31>: 68f000 00000c move y:>$c,r00x00000200 <FACTest+33>: 0a6067        bset #$7,y:(r0) __asm("bclr #7,y:(%0)" : : "A" (M_PDRF)); 0x00000201 <FACTest+34>: 0a6047        bclr #$7,y:(r0)0x00000202 <FACTest+35>: 0af080 0001fe jmp >$1fe  }

 

 


When measured with a scope I am only seeing around 1.167 Mhz from high to high.

 

This seems rather slow!

 

Or is it normal?

 

Thanks

 

Andy

 

Outcomes