Use S32K148 's LPSPI as SLAVE, What is the minimum delay time between CS and SCK.

[lixin_zhou]

HI supporter, 

I have a question.I use IMX8 SPI as master, S32K148 LPSPI as SLAVE（use DMA）.CS & SCK delay time is 100ns. 

When transmission starts, S32K148 always sends data 1 byte slower.

I think maybe CS&SCK delay is too short，But I didn't find minimum delay time in datasheet.

Best regards.

[lixin_zhou]

here is picture for question

[Robin_Shen]

Hi lixin,

Do you want to send data 0x0D from slave to master while master sends the first byte to slave?

If so, please try to fill the data buffer of slave before the master CS pull low and send out the CLK.

Best Regards,
Robin
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[lixin_zhou]

HI Robin ,

I want send 0x0D from slave to master,but I already fill data buffer before CS pull down.

I fill data buffer at A2(BLUE CIRCLE)

I use another chip as the SPI master, CS and SCK delay time is about 70us，the question didn’t occur.

So,Could you tell me when use S32K148 's LPSPI as SLAVE, What is the minimum delay time between CS and SCK? I didn't find it in the datasheet.

Best Regards.

[Robin_Shen · Accepted solution]

tLead Enable lead time(PCS to SPSCK delay) can be found in Table 46 of datasheet.

[lixin_zhou]

HI Robin,

     Could you send me a copy of S32K-DS? 

     I only have S32K-RM .

    Best Regards.

[Robin_Shen]

S32K1xx MCU Family - Data Sheet

[lixin_zhou]

HI Robin,

Thanks a lot!

Best Regards.