MASAL (the Master Logical Entity) used PPT Transceivers rather than EM signals as his communication between modules. This allowed him to grow very large and eventually span the Earth. MASAL controlled all the robots, vehicles, automated equipment and so on. After MASAL invented the 24th chromosome and the Overmind arose, MASAL's PPT Transceivers allowed him to become fully integrated into the Overmind .
MASAL's ultimate plan was to transform humans into living robots. He watched and waited and grew impatient. He instigated a series of disagreements with the Overmind and eventually forced the two to split. This precipitated a war. MASAL turned the robots into deadly weapons and slaughtered a tremendous number of Vuduri. Everything under his control was also used as weapons including airships, ground vehicles and so on.
Eventually, the humans prevailed. MASAL had taken his last refuge (or so the Overmind thought) beneath the Flatirons just outside of Denver. The Vuduri constructed huge PPT cannons and blasted out the mountains. The resulting crater was so huge, it is easily seen from the Moon with the naked eye.
In the aftermath of the war, the Vuduri banned the use of robots forever. Not in space, not under the sea, nowhere on land or on other worlds. A new type of computing device, digital in nature, was invented. Because they were digital, machines like OMCOM could never be integrated into the Overmind so they were permitted limited control of vehicles, starships and so on. With that control, a fundamental law was established: no computer could ever have access to a Casimir Pump or PPT Transceiver again. The fear was that with the vastly increased range of PPT Transceivers, even digital computers could become unleashed, a crime called Tasanceti.
Unfortunately for Rome, the Stareater crisis caused her to have to violate the law and she later paid for this crime by being banished from the Earth. To make matters worse, MASAL wasn't even dead although Rei and Rome eventually corrected that problem.