Idle State of K20 SPI Master Data Output

gvalvo — Wed, 17 Jul 2019 15:24:29 GMT

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.

Re: Idle State of K20 SPI Master Data Output

mjbcswitzerland — Wed, 17 Jul 2019 20:51:18 GMT

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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Re: Idle State of K20 SPI Master Data Output

gvalvo — Wed, 17 Jul 2019 20:58:33 GMT

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

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