INT 2F - Topware Network Operating System - INSTALLATION CHECK
        AX = FF00h
Return: AL = 00h not installed, OK to install
           = 01h not installed, not OK to install
           = FFh installed
SeeAlso: AX=FF01h,AX=FF02h,AX=FF10h,INT 21/AX=FF02h,INT 7A"Topware"

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