Onion Omega2

The Omega2 is the latest in development boards from Onion. It comes packed with built-in Wi-Fi, a Linux Operating System, flexible GPIOs, and a powerful processor, among other things.

The Omega2 at a Glance


Omega2 Specs
Processor 580MHz MIPS CPU
Memory 64MB Memory
Storage 16MB Storage
MicroSD Slot No
WiFi adapter b/g/n Wi-Fi
GPIOs 18
I2C 1
I2S 1

Processor Datasheet

The datasheet for the Omega2’s processor can be found here: Mediatek MT7688 Datasheet

The Pins

Take a look at the Using the GPIOs article to learn more about the Omega’s GPIOs, multiplexing GPIO functionality, and the behaviour and requirements of the Omega’s special GPIOs.


The Operating system

The Omega2 runs the OpenWRT Linux operating system, based on the OpenWRT 18.06 release. OpenWRT is excellent for embedded Linux and networking applications. Included with OpenWRT is the OPKG package manager, that allows easy download and installation of various packages to extend the functionality of your device.

The Omega LED

The Omega’s amber System Status LED provides a visual indication of the Omega’s current state,

State LED Activity
Not powered Off
Booting/Updating Blinking
Up and running On

The Omega LED uses GPIO44, and can be programmed to do a number of cool things. You can learn more about the LED in the article on how to use the Omega’s LED

Reset GPIO

The Omega’s can be reset using GPIO38. When plugged into a Dock (e.g. Expansion Dock), this GPIO gives various functionality to the reset button found on docks. For example, a quick button press triggers the reboot command, whereas holding the button for about 10 seconds will trigger a factory reset command.

The WiFi Antenna

The on-board antenna is a ceramic surface-mount chip antenna. It’s small but packs a punch, the Omega’s WiFi signal is able to travel up to 100m (300ft) line-of-sight outdoors.

The U.FL Connector

Connect an external antenna to the Omega’s male surface-mounted U.FL connector. An external antenna can be used to extend the range of WiFi connectivity or provide a very directional signal. When an external antenna is plugged in, the SMT and external antennas will split the transmission power, providing only half of expected gain. In order to use your external antenna at its maximum performance, you will need to modify your Omega by removing the 0 Ohm resistor that is located between the WiFi antenna and U.FL connector so all the power goes to the external U.FL antenna.

Follow the procedure outlined here to modify your Omega.

DISCLAIMER: Perform any modifications to your device very carefully and at your own risk. This procedure is difficult to undo, and will require the permanent use of an external antenna to have any sort of reasonable WiFi connectivity. If you damage your Omega during this procedure, Onion Corporation is not responsible.

Mechanical Drawing

We’ve made available a detailed diagram of the dimensions and geometry of the Omega2.