An experiment -- Fast GPIO vs normal GPIO

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An experiment -- Fast GPIO vs normal GPIO

An experiment -- Fast GPIO vs normal GPIO

Hi team ,

     I would like to share an experiment that about the Fast IO - zero wait state access of KL series . Detail please refer to attached file .

Best regards,

David

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I have done some experimenting on FRDM-KL02Z32 and have problems with FGPIO switching performance with Bus Clock 4 MHz and below.

The 8MHz Bus Clock works normal 125 ns cycle per FGPIO switch, but with 4 Mhz Bus Clock, I get unstable switching from 250 ns to 500 ns.

To me it looks like System Clock and Bus Clock have synchronization problems.

I checked with FEI and 24 MHz divided down to Bus Clock  and also with IRC 4 MHz directly to Bus Clock in FBI mode same result.

Can someone recheck or explain?

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Last update:
‎12-10-2015 09:29 AM
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