Getting CAN working on a Teensy 3.6

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Teensy 3.6 board. It's tiny!
Teensy 3.6 board. It's tiny!

A Teensy 3.6 is an ideal board for making a CAN-compatible device. It's generally compatible with Arduino sketches and hardware, which makes it relatively simple to go from an Arduino-based prototype to the finished article.

Get Teensyduino

The Teensy IDE is a modified version of the Arduino software. You can download it here. Even though it's a separate program, it will make use of your previously-installed Arduino libraries and sketches. Which is pretty neat.

Connect your CAN transceivers

Teensy 3.6 CAN connections

Good news: you can use the same SN65HVD230-based CAN transceivers that you use with a Due. Connect the TX/RX lines to pins 3 & 4 (CAN0) and pins 33 & 34 (CAN1) as well as GND and 3.3V (see pinout diagram).

Test your CAN link

Connect the CAN bus on the two transceivers together (CANL to CANL, CANH to CANH)

Teensy 3.6 CAN loopback test
Teensy 3.6 CAN loopback test

Connect your computer to the USB port on the Teensy board.

Download the FlexCAN library and install it in Teensyduino with Sketch -> Include Library -> Add .ZIP Library...

Now you can test your CAN communications with:

File -> Examples -> FlexCAN -> CANTest

Sketch -> Upload

Tools -> Serial Monitor

If your CAN transceivers are working properly, you should be rewarded with incrementing numbers in the serial monitor window.

Build your CAN device

Teensy CAN-based ammeter with OLED display
Teensy CAN-based ammeter with OLED display

You can hook up your Teensy to any 3.3V Arduino peripheral to make your device.

The picture shows a simple CAN-based ammeter made from an Isabellenhütte IVT-S and an Adafruit SSD1306 OLED display. The IVT-S CAN bus is connected to the (terminated) CAN0 transceiver and the OLED display is an I2C device connected to SCL (pin 19) and SDA (pin 18). You can find the source code here.

Start hacking with SavvyCAN!

Incredibly, it seems you can use a Teensy with SavvyCAN. Just install TeensyRET with Teensyduino. Once you've uploaded the program, note down the name of your Teensy's USB connection.

In SavvyCAN:

Connection -> Open Connection Window

Add New Device Connection and select the USB connection you noted earlier

Create New Connection

Check "Enable Bus" and set the Speed to match your CAN bus. 500000 is a good guess. You can always change it later.

After a few seconds, you should see "Connected" in the Status field.