Support Question of the Week: How to Filter Data Captures with a Beagle SPI Protocol Analyzer

Q: I am troubleshooting a device that has a TI CC1101 chip that communicates via SPI (serial peripheral interface). I hooked up your Beagle I2C/SPI Protocol Analyzer to the CLK, SI, SO, CSn, GND pins of the chip for data captures, specifically the bootup process.

I am looking to see what the settings are for the registers in the CC1101 chip, specifically register 0x00-0x15. Can I determine this through the capture using Beagle analyzer, or do I need to use an Aardvark I2C/SPI Host Adapter to do that?

A: Thanks for your question! You can use the data filtering options in Data Center Software to locate particular transactions that have been captured. What you are looking for is system specific, but we can show you an example that you can modify for your system.

Beagle IC2/SPI Protocol Analyzer supports filter data captures options Figure 1: Beagle I2C/SPI Low-Cost Protocol Analyzer

For this example, we assume you want to see the data that is written to register 0x13. To do so, have the master send two bytes to the slave: the first byte is the register address followed by one byte of data.  To find this transaction in Data Center software, do the following:

  • Expand all the transactions (click the plus icon below the do the transaction windows) and then update the LiveFilter as follows:
    1. Check the "Not" box next to the MISO Data.  This will hide all the MISO  (master input slave output) transactions since we only care about the data sent from the master to the slave.
    2. Uncheck the "Show parent is child matches" box.  This will hide the top level Transaction records so that only the MOSI (master output slave input) records will show.
    3. Enter the following filter string in the MOSI Data box (excluding the quotes): "^ 13 ? $".  This tells Data Center to look for a 0x13 in the first byte followed by any one single byte.

There are more options to filter data. For details, please refer to section 5.5 of the Data Center manual.

Note that expanding the records and performing steps 1 and 2 do not affect filtering the MOSI data; what is  provided is the convenience of hiding selected records, which supports viewing only the MOSI records.

For more information about our products, guidelines and manuals, please refer to our documents online:

We hope this answers your question. If you have other questions about our protocol analyzers, software tools or other Total Phase products, feel free to email us at sales@totalphase.com  or support@totalphase.com.

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