INT 16 - TurboPower TSRs - INSTALLATION CHECK
        AX = F0F0h
Return: AX = 0F0Fh if installed
            ES:DI -> last data block in TSR list
Note:   the returned TSR list provides support for communication among TSRs
          built with TurboPower's Turbo Professional and Object Professional
          libraries for Turbo Pascal

Format of data block:
Offset  Size    Description
 00h    DWORD   pointer to program tag (counted ASCII string)
 04h    WORD    interface version number (0400h)
 06h    DWORD   pointer to command entry point
 0Ah    DWORD   pointer to previous data block (0000h:0000h if none)
 0Eh    DWORD   pointer to next data block (0000h:0000h if none)
---swappable TSRs only---
 12h    DWORD   pointer to swapping data
 16h    DWORD   pointer to user data
        more???