SPI receive - TI LAUNCHXL-F28379D

Hi Friends,

I'm working in a control project using LAUNCHXL-F28379D. I have installed all the third-party software "TI ControlSuite 3.4.2 / TI CCS 8 / TI C2000ware 1.00.04" and the Simulink Embedded coder support package "Embedded Coder Support Package for Texas Instruments C2000 Processors - version 18.1.0".

I want to receive data from other controller using SPI communication.

To simulate the receiving data, I implemented a loop-back with physical connections: I used SPI-A as master mode to transmit data and SPI-B as slave mode to receive the data. See picture below

Also, see SPI config

The problem is: I always receive data 0 and the status is 0 !!!

what did I do wrong?

Thank you,

Fares Marjieh Control Engineer

Answer 1

[Aditya Padmanabha]

Hi Oleg,

Please use the latest update of the support package - "18.1.2" (in the MATLAB main window go to Add-Ons --> Check for Updates --> Hardware Support Packages) as we made recent changes to the SPI module.

In the above settings, looks like you are trying to use SPI in tri-wire mode. In tri-wire mode, we need to set TALK bit to 1 for transmitting the data and set TALK to 0 for receiving the data. But in our code, we are setting the TALK bit to 1 by default causing SPI to be in transmit mode always.  

We are currently tracking this issue internally. I apologize for the inconvenience caused, we will work on this issue and fix it as soon as possible in the future support package updates.  

I have a workaround to unblock you in the meantime. You can use the custom code with the SPI Transmit and Receive block to set the TALK bit to 1 or 0 before Transmit and Receive block. I have attached one example model for your reference.

Thanks,

Aditya

[Zak Campbell]

Hello fellow C2000 users. I am wondering if the last comment made on this topic still stands as of April 2020. I am using embedded coder support for th C2000 version 19.2.2. I am in need of fixing the 3 wire communications issue I have, where, similar to the problem statement above, I am getting all zeros read out of the peripheral when I am seeing pretty clear data being read out on the o-scope.

Thanks,

Zak