Assembler Code is an interactive software language in the world of the now-defunct City of Heroes MMO.
Created by Bree Valley, it can be used in a variety of functions depending on the device it is installed in.
Assembler Code is adaptive to the hardware it is introduced to. The more technically-complex the device, the more it can do to the device.
For instance, assembler code can re-work a simple cellphone to become a portable radio station. For a phone with a camera, it can broadcast TV signals. For a smartphone, it can become an advanced remote control pad for other devices.
The only limitations of assembler code are the hardware and the programmer.
In 2015, Paragon City was besieged by two threats: the super-powered being Destitution and a swarm of robots that suddenly appeared from various sources, including transforming themselves from certain audio devices created by LexieTech. The robots were also responsible for subverting the city's various networked systems, including the CPCU systems originally developed by the human host of Daybright back in 2009.
Daybright was the one that discovered the presence of Assembler Code and began developing ways to restore control over the city's communication systems.
Assembler Code was first mentioned in "Furia and the Guardians" #3.