s32k lpspi unexpected cs delay in high freq

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s32k lpspi unexpected cs delay in high freq

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1395209008
Contributor I

s32k144EVB board and s32k_sdk

i got a problem when using lpspi2:when i set a higher freq like 12Mhz ,there are about 90us delay betwwen sck and pcs deassert. but 600khz freq seems ok, the most strange thing is that master setting in 12Mhz freq is almost the same with settings in 600khz freq.

wave and register seetings attached below

this is my first question in community , plz help thx  

0x4002e010: 0x00000001 0x00000701 0x00001c02 0x00000000
0x4002e020: 0x00000000 0x00000003 8
0x4002e030: 0x00000000 0x00000000 
0x4002e040: 0x2f2f2e02 
0x4002e058: 0x00000002 0x00000000 

0x4002e060: 0xc120001f 
0x4002e070: 0x00000002 0x00000000 
12M
------------------------------------------------------------------------------------------------------
600k
0x4002e010: 0x00000001 0x00000701 0x00001c02 0x00000000
0x4002e020: 0x00000000 0x00000003 
0x4002e030: 0x00000000 0x00000000 
0x4002e040: 0x2f2f2e4e 
0x4002e058: 0x00000002 0x00000000 
0x4002e060: 0xc120001f 
0x4002e070: 0x00000002 0x00000000 

600k.PNG12M.PNG

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danielmartynek
NXP TechSupport
NXP TechSupport

Hello 1395209008@qq.com,

I can't reproduce this delay.

Could you please share a whole test project so that I can easily reproduce this behavior on my side?

Thanks,

BR, Daniel

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1395209008
Contributor I

its hard to share my whole project, cause i also use zephyr os in my project.  in my view, this cs delay is disaccrod with these register settings, what do u think and could u share some possible reason about this issue? 

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danielmartynek
NXP TechSupport
NXP TechSupport

Hello 1395209008@qq.com,

I understand that you are using the LPSPI SDK driver.

Do you use blocking or non-blocking transfer functions?

At 12 MHz, are all the data sent and received correctly?

Do you see any error state?

Thanks you,

BR, Daniel

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1395209008
Contributor I

all data send and recv ok,and i am using the non-blocking SDK API

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