qa.hlp (Table of Contents; Topic list)
Int 21H Function 63H
   Summary  Notes  Back
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▀ The lead byte table consists of a variable number of 2-byte entries, ter-
  minated by 2 null (00H) bytes. Each pair defines the beginning and ending
  value for a range of lead bytes. The value of a legal lead byte is always
  in the range 80-0FFH.
 
▀ Entries in the lead byte table must be in ascending order. If no legal
  lead bytes are defined in a given system, the table consists only of the
  two null bytes.
 
▀ If the interim console flag is set, Int 21H Functions 07H (Unfiltered
  Character Input), 08H (Character Input without Echo), and 0BH (Keyboard
  Status) will support interim characters.
 
▀ Unlike most other MS-DOS services, this function call does not necessar-
  ily preserve any registers except SS:SP.
 
▀ [4.0] The address of the DBCS lead byte table can also be obtained with
  Int 21H Function 65H.
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