Roomblock is controlled by a Raspberry Pi. As you know, Raspberry Pi is low cost ARM based board computer. We use Raspberry Pi 2, Ubuntu and ROS are installed on it.
Raspberry Pi 2
The ROI connector on the Roomba and Roomblock are connected with a USB-serial adapter cable.
USB-Serial adapter cable
We share how to build Roomblock at Instructables. Please try it at your own risk.