SPI

[Mark_Y]

Hi all:

At the speed of 8Mbps, the test to send and read 2byte of data takes about 9 us， and I think it's a little time-consuming. Have you tested the rate of SPI? The following is my code, is there any problem with writing it like this:

And the "spi_xfer_done" will  be changed to true in the callback function. Thanks!

[Einarh]

Hello

How have you measured this?

Have you tried measuring while sending more data at a time?

Best regards,

Einar

[Mark_Y]

Hi:

I used an oscilloscope to measure this result. When  I send one byte and recive 13 bytes, it takes 19us.

Thanks!

[Einarh]

8 Mbps is the SPI data rate.

Instead of measuring how long it takes to "send and receive a number of bytes", you should measure the data rate while the SPI is actually transferring data.

Transferring 14 bytes in 19us corresponds to a data rate of ~5,9 Mbps, which doesn't seem too far off considering overhead.

-Einar