BBC Micro depth, resolution and memory economy. In the first models, the OS and applications were left with the RAM left over from the display mode. Mode 7 was a Teletext mode, extremely economical on memory and an original requirement due to the BBC's own use of broadcast teletext (Ceefax). It also made the computer useful as a Prestel terminal. The teletext characters were generated on board, for use with monitors and TV sets without a Teletext receiver. Train time displays at UK stations were driven by BBC Master computers in this mode until around the late 1990s. Mode 7 used only
Teletext comparable to systems such as France's Minitel. The modem was asymmetric, with data sent at 75-bit/s, and received at 1200-bit/s. This two-way nature allowed pages to be served on request, in contrast to the TV-based systems' sequential rolling method. It also meant that a limited number of extra services were available such as booking event or train tickets and a limited amount of online banking. Teletext information is broadcast in the vertical blanking interval between image frames in a broadcast television signal, in numbered "pages." Teletext allows up to eight 'magazines' to be broadcast, identified by the first digit of