bas7qck.hlp (Table of Contents; Topic list)
INKEY$ Function
  Syntax  Details  Example                 Contents  Index  Back
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INKEY$
 
Returns
    A 1- or 2-byte string that contains a character read from the
    standard input device, which usually is the keyboard:
 
    ■ A null string is returned if there is no character to return.
    ■ A one-character string contains the actual character read.
    ■ A two-character string indicates an extended ASCII code, the first
      character of which is hexadecimal 00.
 
See Keyboard Scan Codes and the ASCII Character Codes
for a complete list of character codes that can be returned by the INKEY$
function.