10.3 Raw mode

     The IBM PC keyboard generates two characters for every key you
     press. The first character is called the ASCII code, and the
     second character is called the scan code. Only the ASCII code is
     transmitted to the remote system by default. There are, however,
     some situations which require the Terminal software to transmit
     both codes. The AVATAR emulation protocol and the Doorway
     programs both require the complete codes (two characters) to
     identify certain keys; function and arrow keys in particular.

     Once raw mode has been enabled (by pressing the Scroll Lock key),
     you cannot reach any of the Terminal's regular functions. Raw
     mode is disabled by deactivating Scroll Lock.