INT 13 - FAST! v4.02+ - API
        AH = 80h
        CX = 6572h
        DX = 1970h
        ES:BX -> request packet (see below)
        AL = function
            01h get cache information (see separate entry)
            04h disable cache
            05h enable cache and reset statistics
            06h installation check (see separate entry)
            07h unhook interrupts (see separate entry)
            09h flush cache
            0Ah (v4.02+) enable staged writes
            0Bh (v4.02+) disable staged writes
            0Ch (v4.02+) enable beep on flush
            0Dh (v4.02+) disable beep on flush
            0Eh ???
            0Fh ???
            10h (v4.12+) enable hotkeys
            11h (v4.12+) disable hotkeys
            12h (v4.13+) set idle delay
            13h (v4.13+) set flush dirty percentage
            14h (v5.00+) enable mouse checks
            15h (v5.00+) disable mouse checks
            16h (v5.00d+) reduce cache size to minimum
            17h (v5.00d+) increase cache size to maximum
Return: AH = status (except function 06h)
            00h if successful
            01h invalid function
            05h not supported by the installed variant
        CF clear if successful
        CF set on error
        AL may be destroyed
Program: FAST! is a disk cache by Future Computing Systems and marketed by BLOC
          Publishing Corp.
SeeAlso: AX=8001h,AX=8006h,AX=8007h
Index:  hotkeys;FAST!

Format of request packet:
Offset  Size    Description
 00h    DWORD   pointer to 19-byte signature string (see below)
 04h    DWORD   pointer to buffer for data (if needed by function)

Values for v4.04-v5.03 signature string:
 13h 07h 06h 08h 11h 18h 0Fh 0Eh 02h 18h 13h 08h 0Bh 08h 01h 00h 04h 08h 15h

.