Digital terminals for packet broadcasting

Roberts illustrated the potential use of packet switching technology by postulating a personal computer terminal using radio broadcasting to connect the user to a computer. The proposed terminal had a unique five-finger keyboard and plasma-discharge display. The keyboard would generate and send characters, one at a time, to the computer using 64 bit packets per character. The computer could convert these to a 35-bit (5X7) pattern and retransmit a 144-bit packet to the terminal to control a 5 X 7 dot matrix character. Thus, the terminal needed no character generation logic and only a minimum of digital control logic to interface keyboard and display to a radio modem. This was a reasonable concept insofar as the terminal was intended to operate within a short distance of the computer to accommodate low-power radios, and so long as only a few terminals were in use.