When building embedded systems, the size of your board is always a consideration. The design of a product can be ruined by the need for a large, cumbersome PCB and its enclosure sticking out like Quasimodo’s defining characteristic. The Onion Omega2 line looks to keep your form factor in check with small systems that pack a big punch.
The Omega2 line of boards is made up of the Omega2, Omega2+, and the Omega2S. While the Omega2 and 2S share the same basic specs, the 2+ doubles the RAM (16MB vs 32MB) and storage (64MB vs 128MB) and adds a built in microSD slot for additional storage. These are embedded Linux boards and come pre-loaded with firmware, making setup easy. All boards have 15 GPIO pins and a number of other pins broken out, such as USB and ethernet. For our testing, Onion sent us the 2+ version of the board.
At outward appearances alone, I can’t help but compare the Omega2+ to the now discontinued Intel Edison board. Both are about the size of two postage stamps, with their real guts covered by a thin protective metal shell. Unlike the Edison and its annoying bottom connector, the Omega2 boards have standard pin spacing on the sides, making them very easy to interface with. For those ready to lock their design into place, the Omega2S is a surface mount option with the same pin spacing but no pins, which makes it easy to solder into place on a custom PCB.
The setup process was simple but I found it to be a little buggy. To get started, you plug in your Omega2+ to a USB power supply (even your computer is fine as it doesn’t draw much power), then connect to the Wi-Fi access point it creates once booted up. A wizard that is accessible via your computer’s web browser will guide you through putting your device on your network and updating the software. I had problems connecting to my network using the built-in chip antenna, and had to add an external antenna to get it to connect (there is a socket, but the unit doesn’t ship with an antenna). Even with the additional antenna, the network seemed a bit flaky — dropping me a few times until I had fully upgraded the software.
One of the big draws for the Onion boards is the Onion cloud. Adding your device to the cloud makes it easy to interact with it from anywhere in the world. On my home network, I was able to control my Omega2+ via the web without needing to punch any holes in my router or firewall. The web interface even has simple graphical apps to send commands to boards with just a click of the mouse.
For those who don’t want to roll their own carrier board, or who want to start prototyping their project quickly, Onion has a decent selection of stackable proto boards. I added the relay and OLED screen boards to my stack and was able to quickly send commands to them via the web interface, spitting out words and images to the screen, and making the relays clack away as I turned them on and off. I was impressed at how easy this all was with no real configuration. Simply plug in the boards, download the relay and display module from the web interface, and I was up and running.
I would love to see the Onion boards take a deeper look at their Wi-Fi (of course this could just be my board) and try to make sure the setup process can more easily recover if they don’t complete correctly, but I think the Omega2 family of boards are a great way to get started in IoT development. With the Onion cloud there to help you, much of the hard work is already done.