SPI Master clock set to about 8 MHZ in KL25Z

arthshah — Wed, 17 May 2017 09:41:08 GMT

kerryzhou‌

hello,

i am working on KL25Z.

i need to set SPI Clock rate about 8 MHz how can i set this ?

In SPI BR register i can not set to 8 MHz..

Re: SPI Master clock set to about 8 MHZ in KL25Z

kerryzhou — Thu, 18 May 2017 10:34:24 GMT

Hello Arth Shah,

You can use the SPI1, the clock source is the system clock, the system clock can up to 48Mhz, let's take system clock = 48Mhz as an example.

Now, follow this picture to calculate the SPPR and SPR.

8Mhz= 48M/(SPPR+1)*2^(SPR+1)

So, SPPR=2, SPR=0 can get 8Mhz baudrate.

You can configure SPI1_BR=0X20.

If your bus is 24Mhz, you can't use the SPI0 get 8Mhz, SPI0 clock source is bus clock.

Wish it helps you!

Have a great day,
Kerry

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topic Re: SPI Master clock set to about 8 MHZ in KL25Z in Kinetis Microcontrollers

SPI Master clock set to about 8 MHZ in KL25Z

Re: SPI Master clock set to about 8 MHZ in KL25Z