Use IRCLK for SPI communication on MPC5775K

[hqliu]

Hello,

I'm working on MPC5775K with an external clock synthesizer. The synthesizer needs to be configured by SPI interface before it can output any clock signal. So I have to config it using MPC5775K with IRCLK. Would please let me know the correct register configuration process of the operation? This is the operation flow I need:

1) MPC5775K running on IRCLK. Config clock synthesizer through SPI.

2) Change clock source of MPC5775K to 40MHz external clock from clock synthesizer.

3) Config PLL0 of MPC5775K and make peripherals working.

4) Config SDPLL to enable AFE.

It's appreciate if a example code can be shared.

Thanks. 

[martin_kovar]

Hello,

1) MPC5775K runs on IRC clock by default. So you cannot configure this on your own. But you must enable SPI module. Please see PinToggleStationery example and eventually DSPI example.

Example MPC5775K PinToggleStationery S32DS 

https://community.nxp.com/docs/DOC-332744 

2) This can be also found in example above. you must switch on FXOSC and also bypass mode.

3) PLL0 configuration is also included in the example above.

4) Unfortunately, we do not have any example, how to configure SDPLL.

Hope it helps a little bit.

Regards,

Martin