INT 67h,  43h  GET HANDLE AND ALLOCATE MEMORY

On entry:
        AH = 43h
        BX = number of logical pages to allocate

Return:
        AH = status
            00h function successful
                DX = handle
            80h internal error
            81h hardware malfunction
            84h undefined function requested
            85h no more handles available
            87h more pages requested than physically exist
            88h more pages requested than currently available
            89h zero pages requested