S32k144 spi increase speed

[nanjun]

Hello,

In while loop, LPSPI_DRV_SlaveTransferBlocking() is used to reveive data without the activation of DMA. The max. data rate reaches only 1.5Mbit by testing. the receve buffer will be 0 if data rate is further increased. The waveform is good when osci is used to check.

Principally, the data rate should reach 14Mbit shown in datasheet. How the data rate can be increased?

Kind regards,

Neo

[Jeremy_He · Accepted solution]

Hi Neo, 

It can reach 14MHZ for MCU is running in HSRUN mode, for normal RUN mode, it can only reach 10MHZ maxim.

If you want to achieve the highest efficiency, you may try the bare-metal code(

https://www.nxp.com.cn/docs/en/application-note/AN5413.pdf).  Since the SDK will maintain the global state and do a few extra things so the SDK is not the most efficient choice if you want to achieve the best SPI transfer performance. Another tip is to increase the optimization level of the compiler.

Best wishes,

Jeremy