ECE497 CAN Cape

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thumb‎ Embedded Linux Class by Mark A. Yoder

Team members: David Mehl and Sabeeh Khan

Grading Template

I'm using the following template to grade. Each slot is 10 points. 0 = Missing, 5=OK, 10=Wow!

00 Executive Summary
00 Installation Instructions 
00 User Instructions
00 Highlights
00 Theory of Operation
00 Work Breakdown
00 Future Work
00 Conclusions
00 Demo
00 Late
Comments: I'm looking forward to seeing this.

Score:  10/100

(Inline Comment)

Executive Summary

Our project combines a cape circuit board design with the necessary software to configure the Beaglebone Black in order to view the messages on a CAN bus using the can-utils package. The use of jumpers allows for the cape to be adaptable to different situations (such as CAN development, sniffing a vehicle bus, evaluating CAN transceivers, etc) by allowing the user to select whether or not to use a terminating resistor, 3.3V or 5V for the transceiver chip Vcc, and if they would like an OBD-II signal ground to be connected to the ground pour of the board.

The second revision of the circuit board has been tested and is fully functioning as expected, and the configuration script is setting up the pins properly. We were able to read the CAN messages off of a homemade CAN bus built out of two dsPIC33EV256GM102 microcontrollers, and we were able to read the CAN messages off of a 2012 Mazda CX-5. We have used a couple different CAN transceivers and achieved success with both.

This CAN cape will be an excellent tool for anyone wishing to look at CAN communication traffic on a bus or attempting to explore CAN system development. It will be flexible enough to meet almost all CAN development needs with only minor adjustments required to the setup steps to achieve different functionality (active bus participant vs. spy, setting bitrate, etc).


This project includes a printed circuit board. The project files can be found in the Github repository. The schematic symbols and part footprints are also found in the repo.

Installation Instructions

The installation of this project is relatively simple. First, begin by cloning the github repository:

beagle$ git clone

Next, run the installation script included in the repo. The installation script installs the linux package 'can-utils' on the beaglebone. This package has the software necessary to make sense of the messages on the bus and provides a display interface:

beagle$ cd Beaglebone-CAN-cape/
beagle$ ./

Then, be sure you are operating as root, and then source the setup script. This will configure the pin muxes for dcan1, which operates on P9_24 and P9_26. It also uses P8_13 to control the CAN transceiver STANDBY pin. Then it sets up the interface can1. You must provide the bitrate of the CAN bus as an argument, replacing 'BITRATE' in the command below. If you are developing your own network, you should know this value as you should have selected it. If you are attempting to sniff a production vehicle, your best bet is to start with 500000, which is representative of 500 kbps. If this doesn't work, try a google search to see if you can find the bitrate:

beagle$ source BITRATE

After the above steps complete successfully, the can1 interface should be up and running. You can confirm this by running:


You should see an interface 'can1' and, if you have connected to a bus and have entered the correct bitrate, you should see an RX count above 0.

Give step by step instructions on how to install your project.

  • Include your github path as a link like this to the read-only git site:
  • Be sure your is includes an up-to-date and clear description of your project so that someone who comes across you git repository can quickly learn what you did and how they can reproduce it.
  • Include a Makefile for you code.
  • Include any additional packages installed via opkg.
  • Include kernel mods.
  • If there is extra hardware needed, include links to where it can be obtained.

User Instructions

Once everything is installed, how do you use the program? Give details here, so if you have a long user manual, link to it here.


Here is where you brag about what your project can do.

Include a YouTube demo.

Theory of Operation

Give a high level overview of the structure of your software. Are you using GStreamer? Show a diagram of the pipeline. Are you running multiple tasks? Show what they do and how they interact.

Work Breakdown

Create PCB Footprints: Sabeeh and David

Create Schematic: David

Create PCB Layout: David

Explore Device Tree Overlays: Sabeeh

Create Setup Script: Sabeeh

Verify First Revision PCB: Sabeeh and David

Verify Second Revision PCB: Sabeeh and David

Verify Overall Functionality: Work in Progress, target date 11/8/16

Enhance User Interface: Time permitting, target date 11/10/16

Future Work

Suggest addition things that could be done with this project.


Give some concluding thoughts about the project. Suggest some future additions that could make it even more interesting.

thumb‎ Embedded Linux Class by Mark A. Yoder