IWR1443: Interpreting data from the serial port

Dexter Banham

Part Number: IWR1443

Hello everyone,

I'm currently been experimenting with the TI IWR1443 and its documentation.

I'm running the board with the latest firmware for the mmWave demo (01.00.00.05),

I've been able to view the output on the web-based GUI and send commands both over the GUI and serial. However, I would prefer to analyze the data and log it in my own program. I've put together a little python program that can send configurations to the board and pick up the data from the COM port (Data). At the moment I am using the default configuration commands from the SDK and am sending data over the UART serial. I'm picking up 672-byte packets with the 8 bytes "4* Magic Words" at the start of the header.

I'm wondering if anyone at TI can provide more concise documentation for the data structure of the packets which explains how to decode them into useful information? I’m aware the existing documentation does in principle explain how to decode the data, but singe concise document detailing the packet structure would be helpful. An example Matlab or another script which demonstrates decoding the data would be even more helpful – does one exist?

While I'm aware that there are other ways to get data off the board, the serial port is at the moment best suited for my needs.

Thanks in advance for any help provided,

Best regards,

Dexter

over 8 years ago

0 Vaibhav Mahimkar over 8 years ago

TI__Mastermind 23725 points

Hello Dexter,

We are working on a good format to explain this.

In the mean time please check this post for format description.

e2e.ti.com/.../2250273

Thank you,
Vaibhav

0 Will_Wang over 8 years ago

Prodigy 200 points

Hi Dexter

This picture may help you a lot. I have figured format out via this picture and Interpreted data from the serial port.

0 Will_Wang over 8 years ago in reply to Vaibhav Mahimkar

Prodigy 200 points

Hi Vaibhav

I am encoding my own upper program by reference to Demo_Visualizer to analyse the data captured from serial port in my own application.

It seems that the data is send out frame by frame in period.

However, I do not understand the operation mechanism of Demo_Visualizer and am unable to receive data from serial port correctly.

Can you give me an advice on capturing frame data from serial in real time?( Matlab program)

Thank you,

-Will

0 Dexter Banham over 8 years ago in reply to Will_Wang

Prodigy 70 points

Dear Will,

I have done something similar with Python, rather than Matlab.

Each packet varies in length depending on the number of objects detected, however, each packet must be a multiple of 32 and starts with the 4 * 2byte magic words. The magic word allows you to determine the start of a packet in the byte stream followed by the magic word is the header outlining some basic info about the packet.

Each packet consists of a header followed by two 4 byte numbers that identify the start of the TLV, what data it records and its length in bytes. This allows you to separate each packet into its TLVs, the header records the number of TLVs in the packet.

Depending on what config commands are sent over the UART, the number and type of TLVs do change, however, the overall packet structure remains the same. The documentation is difficult to understand, so I hope I've helped outline what I've found out.

-Dexter

PS: the data comes through backward, each variable should be read from right to left.

0 Kevin Ortiz over 8 years ago in reply to Dexter Banham

TI__Expert 3525 points

Hi,

Dexter, you are correct. That is a good summary of the data structure. As Vaibhav mentioned, we hope the document we are developing provides a clearer description.

Regards,
Kevin

0 Will_Wang over 8 years ago in reply to Dexter Banham

Prodigy 200 points

Hello Dexter

Thanks for your detailed description. You are correct about describing the packet structure.

I have realized reading data via matlab.

I am working on controlling the mmWave device via external MCU.

Regards

-Will

0 Johannes Sedlmeier over 8 years ago in reply to Vaibhav Mahimkar

Prodigy 105 points

Hello Vaibhav,

is the documentation already finisched yet? Because I've the same problem. My MATLAB-Code is already finished to send sensor commands and receive the raw data. But now i need a better documentation to extract the reflexion point coordinates of the result data flow.

BR Johannes