• 0
Sign in to follow this  
MarcusD

Analog Discovery 2 - Problems with higher SPI rates

Question

I am trying to use the WaveForms SPI Logger function to establish a communication between a STM32 and my PC. Everything works fine if I use slow SPI clockrates (slower than ~1Mhz) but I need rates up to 2.5 Mhz (or at least 1.3 Mhz). Is the Analog Discovery 2 even capabel of reading these fast pin changes? Are maybe my settings incorrect?

I don't have any problems with clockrates of 320 kHz or 640 kHz, but WaveForms is just showing me rubbish at 1.25 Mhz, as you can see in the Screenshot. I would have expected to see the letters "ABC" which I am sending currently from the master.

spi_prob.png.49f0cfc32332b4613dbb1b351913ddb4.png

Share this post


Link to post
Share on other sites

3 answers to this question

Recommended Posts

  • 0

Hi @MarcusD

You have set the trigger position far out on the right, -2.3ms. In order to capture with such settings the application is performing digital zoom, reducing the sample rate.
Set trigger position closer to zero or positive, on the left side.

You can select the 4th device configuration to have more buffer:
image.png.38e5d77c2f94c47d45dfaf709dcdef66.png

 

To capture even more data use the record mode:

image.thumb.png.a3825a5e5dadb994120ad2297928efbc.png

 

In case you are not interested in timing you can use the Protocol tool to log SPI data:
image.png.ad3837b32ab65a5ea6562edd186d91f8.png

Share this post


Link to post
Share on other sites
  • 0

Hello attila! Thank you so much! That fixed my problem. In the end I was just too silly to use the program correctly!

It looks like this now:

SPI_LOGIC.thumb.png.4170b803aef352b6e012b2ef8552c26f.png

 

I do not have any further questions. Thank you for your help though! I am very happy with the AD2 and also with the software.

Kind regards!

Edited by MarcusD

Share this post


Link to post
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
Sign in to follow this