DRV8301 SPI Communication, no answer from DRV8301

Hi Markus,

Can you try framing each 16 bit transaction with nSCS instead of the entire sequence?

Ensure that there is an external pull up on SDO.

Are MISO and MOSI correctly labeled? This waveform shows activity on SLAVE OUT but not SLAVE IN.

Hello, 

Thanks for the quick rely.

What do you mean with framing each 16bit transaction?

Why do we need a Pull- up on SDO? Are you talking about the uC SDO PIN oder the DRV8301 SDO PIN (MISO or MOSI?)? in all the years we work with SPI, we never saw Pull- up resistors on any line.

Sorry for the confusion, the MISO and MOSI are swopped. connected the logic analyzer the wrong may around.

Best Regards

Markus

Hi Markus,

By framing I mean to take nSCS back high after the 16 bits are sent. Page 22 of the datasheet has additional information on this.

Transaction sequence would be

• nSCS HIGH->LOW
• SCLK (16 edges, 16 data points)
• nSCS LOW->HIGH

The shift register of the DRV8301 watches for the LOW->HIGH transition of nSCS before it processes the command.

Sorry, this was my misunderstanding on SDO. Please ignore the pull up comment.

Hello Nicholas

I swopped MOSI and MISO to the right PINs.

I make the frameing as you described it in the post above (Set CS high after the 16 bits are sent) But i still don't get an answer from the DRV8301.

Anything I still do wrong?

Hello Nicholas,

I solved the problem today,

The issue was from my side, did not configure the uC SDI PIN correct. Sorry for that!

Hi Markus,

Good to hear! Let us know if you have any further questions.