AH = DAh: Get/Set CodePage

This service provides the capability to get or set the CodePage variable that is examined by the BIOS during soft font loading.

The choices for built-in code pages are:

       Code Page: 437h   850h          852h    860h      863h           865h 
       ------------------------------------------------------------------------
       Country  : US     Multilingual  Slavic  Portugal  Canada-French  Norway

• Input: AH = DAh
  AL = Direction (0 = Get, Else = Set)
  BX = CodePage (If AL#0)
  

• Output: If Get, AX = CodePage
  Else, CodePage set from BX
  

• Registers modified: AX, FLAGS