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Clock speed stm32f429i example package

NSemrHomeInit
Senior

Dear ST Hello,

could you tell me please the real clock value set in this example,

\STM32Cube\Repository\STM32Cube_FW_F4_V1.25.1\Projects\STM32F429I-Discovery\Examples\SPI\SPI_FullDuplex_ComDMA

The clock frequency between master and slave must be equal, does the frequency communication is imposed by the master since they have to be the same?

Thank you in advance,

S.Tarik,

1 ACCEPTED SOLUTION

Accepted Solutions

It depends on the DSP used.

You can configure the baude rate of CR register (calculate APB1/baud rate configured, APB2/baud rate).

In fact, the prescaler define the SPI BUS clock.

0693W000004J9XhQAK.png

When your question is answered, please close this topic by clicking "Accept as Solution".
Thanks
Imen

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6 REPLIES 6
Imen.D
ST Employee

Hello @NSemrHomeInit​ ,

The clock is imposed by the master.

What do you mean by real clock w the baudrate is configured in SPIx_CR1 register ?

Imen

When your question is answered, please close this topic by clicking "Accept as Solution".
Thanks
Imen
NSemrHomeInit
Senior

Hello Imen,

I am trying an SPI communication between the two boards, DSP and STM32F.

Do i have to configure the clock of the DSP the same as the SMT32F?

I have two microcontroller, both are clock configured, but in the end, the master clock will be considered as a clock for the spi bus.

The master supplies the only clock and the transmit/receive is symmetrical, but can occur on different clock edges.​

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It depends on the DSP used.

You can configure the baude rate of CR register (calculate APB1/baud rate configured, APB2/baud rate).

In fact, the prescaler define the SPI BUS clock.

0693W000004J9XhQAK.png

When your question is answered, please close this topic by clicking "Accept as Solution".
Thanks
Imen

Imen,

Thank you very much.

its very clear.

Thank you clive1 🙂