AnsweredAssumed Answered

M4 gpio access time is too long....

Question asked by seohwan on Apr 22, 2014
Latest reply on May 2, 2014 by Ross Mcluckie

Dear Vybrid Expert...

 

I am in trouble with gpio speed...

 

M4 system clock is 66Mhz... and I tested set/clear gpio PTB15...

 

I measured  the time Port on and Port off....about 200nsec or little more...

 

and there are nothing code between Port on and Port off...

 

if cache is enabled the time is little shorter...but I can't understood myself..

 

I gusess..time is so much needed that M4 access GPIO registers..

 

M4 is running on MQX...and in asm file...there are nothing code except port action code..

 

I think I am missing something about this condition.....

 

Please Help me....

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