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Getting Started with the SJTwo

If you are using the SJTwo board this guide will be the simplest guide to getting it up and running. If you are not using an SJTwo board, skip to the next guide in the sequence.

Building and Loading the "Hello World" Application

Step 0: Move into project

cd projects/hello_world/

Step 1: Build project

make application

This will take all of the relevant source code files to your project and generate a binary file that can be loaded onto your board. These files can be found in the build/application folder with the project.


use the make by itself to get additional information on the different features of the build script.


To build for a different board you can specify the platform like so: make application PLATFORM=lpc17xx. This example will build the project for the SJOne board or any other device with an lpc17xx microcontroller on it.

Step 2: Flash board

Before you can flash your board you will need to connect the SJTwo board to your computer using a USB Micro cable. Once connected, to load the binary file into your board, run:

make flash

If you want to specify the device port you can try:

For Ubuntu:

make flash PORT=/dev/ttyUSB0

For Mac OSX:

make flash PORT=/dev/tty.SLAB_USBtoUART


If make flash could not find your device, try running it again. If it continues to fail then it could a few things such as:

  1. Confirm that the USB micro cable is plugged into the computer and the SJTwo board.
  2. Make sure that the USB micro cable supports data communication as some "security" based USB micro cables are designed to only allow charging but do not have data lines.
  3. Make sure that the device is not connected to any computer programs such as Telemetry, PuTTY, or minicom. If you are uncertain of this, disconnecting and reconnecting the USB cable will force the programs to disconnect from the device.
  4. Make sure that the CP2102n driver is installed on your machine. Ubuntu has it preinstalled. For OSX a google search for "CP2102n driver for " will point you to download sites for the driver.

Step 3: Interacting with device

To view the serial output messages from board and interact with it, go to the following URL and following the setup instructions: Telemetry

After falling the web app instructions:

  1. Set the drop down menu for the baud rate 38400 (very important)
  2. Use the drop down menu on the upper right hand side page to the serial port that was used for flashing. Typically this is /dev/ttyUSB0 or /dev/ttyS3 or /dev/tty.SLAB_USBtoUART.
  3. Press the Connect button.