INT 7D - HyperPAD v2.2 - API ACCESS
Note:   this vector is hooked but immediately passed on (without checking
          whether the previous handler was 0000h:0000h).  The sole purpose of
          this vector is to provide the address of the data area described
          below.

Format of HyperPAD data area:
Offset  Size    Description
 -16h   DWORD   pointer to ??? FAR function
 -12h   DWORD   pointer to callback setting function
                [C calling conventions, (*callback)(int (_loadds far *)()) ]
 -0Eh 6 BYTEs   signature "BRC001"
 -08h   DWORD   pointer to previous INT 7D handler
 -04h   DWORD   pointer to ??? data
 00h            HyperPAD INT 7D handler