Idle State of K20 SPI Master Data Output

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Idle State of K20 SPI Master Data Output

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gvalvo
Contributor I

Hi All.

Anyone know of a way to force the K20's SPI Master Data output (Master SOUT) to idle in the LOW state rather than HIGH?

Thanks.

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mjbcswitzerland
Specialist V

Hi

The SPI_SOUT line drives always and holds the state that it drove during the last bit of a transmitted word - therefore it may be at '0' or at '1' between transmissions.

In order to control the state you need to reconfigure the pin as GPIO output and set the state that you need to have, and then set the pin back to SPI mode before sending the following data.

Regards

Mark


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gvalvo
Contributor I

Thanks for the reply, but both the datasheet and my measurements clearly show the Master SOUT line always being driven HIGH between SPI Frames:

SPI.JPG

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