I have a core clock of 178.128 MHz and I would like to set the SDHC clock below 50 MHz. Can that be done using MCUXpresso?

[calvinday]

If so. How?

[calvinday]

K66

[Alice_Yang]

Hello Calvin,

Yes, of course . The SDHC module has four possible clock sources for the external clock source, as
shown in the following figure.

So if the core clock is 178.128 MHZ, you can select the other sources .

For example , the OSERCLK :

Hope it helps

Have a great day,
TIC

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[calvinday]

I was hoping to get a clock closer to 50 MHz. My oscer clock speed is 16.384 MHz. If I select the core clock, I get an error.

[Alice_Yang · Accepted solution]

Hello Calvin,

- From the SDHC clock source diagram we can see, if you select the core clock as the clock

source of SDHC , there isn't division factor  , so 178.128 MHz can't division to 50MHZ.

- I think here maybe you can choose the IRC48MCLK as the clock source :

Have a great day,
TIC

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[calvinday]

Yes. That will work.

[Alice_Yang]

Hello Calvin,

Could you please tell us the part number of your chip, thanks .

Have a great day,
TIC