Int 2F Fn DA00  - Zyxel Zfax V1.x - Installation Check                     [F]

   AX = DA00h

Return: AH = enabled state (00h = enabled, 01h = disabled)
   AL = 5Ah installed
Program: ZFAX is the bundled FAX software which comes with the ZyXEL model
     fax modems.

Note:  This function, and the other DAxxh functions, may apply only to version
     1 of the software; see AX=DB00h for the version 2 installation check

See Also: AX=CBDCh,AX=DA01h,AX=DA02h,AX=DA03h,AX=DB00h