How Do I Capture Only MOSI Data from SPI Traffic?

Question from the Customer:

I am using a Beagle I2C/SPI Protocol Analyzer to look at SPI traffic. I want to capture on only records where MOSI data matches 01 00 00 00. How can I do that?

Configuration Error for filtering MOSI data

Figure 1: Data Center – customer configuration

Response from Technical Support:

Thanks for the question! For your setup, you will need to configure the settings on the Data Center Software for both MOSI and MISO. Following is information about how it works and how to apply the configuration that you want.

How it works:

MOSI data and MISO data are part of one single transaction. However, in the captured trace they are treated as separate records.

The “Not”box on the Filter tab in the Navigator pane acts as an inverse condition when checked. In this case, if the MISO “Not” box is left unchecked and the data box is also left empty, it will act as a wild card; everything will be displayed. When the box is checked, it acts as an inverse and filters out the MISO data.

How to do it:

Here are the instructions. The setup is shown in Figure 2 below, along with an example of the data output you’re looking for.

  1. Enter '01 00 00 00' in the text box next to MOSI Data label
  2. Select the “Not” check box next to the MISO Data label
  3. Ensure that the Enable/Disable applied filter is on (the check sign just above the 'LiveFilter' tab must be green)

Additionally, by hovering over any of the data fields, a tool tip will appear that offers wild cards that can be used to create more flexible filters. How to set the filter on the Data Center Software to capture only the MOSI data of SPI traffic.

Confiture Data Center to filter and capture MOSI data

Figure 2: Data Center – Filter Configuration

We hope this answers your question. Additional resources that you may find helpful include the following:

If you have questions about our Total Phase products, feel free to email us at sales@totalphase.com, or if you already own one of our devices and have a technical question, please submit a request for technical support.

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