INT 21 - Greg Shenaut ASPITAPE.SYS - INTERFACE                                  
	AX = 440Ch
	BX = device handle
	CH = category code
	    07h tape (ASPITAPE.SYS)
	CL = function
	    01h "mtop" - perform tape operation
	    02h "mtget" - get tape status
	    03h ignore end-of-tape errors
	    04h enable end-of-tape errors
	DS:DX -> parameter block (see #01554,#01555)
Return: CF set on error
	    AX = error code (see #01680 at AH=59h/BX=0000h)
	CF clear if successful
	    DS:DX -> data block
Notes:	This device driver is a simple DOS interface to the Adaptec Advanced
	  SCSI(Small Computer Systems Interface) A system-independent expansion bus typically used to connect hard disks, tape drives, and CD-ROMs to a computer.	A host adapter connects the SCSI bus to the computer's own bus.  See also ESDI, IDE. Programming Interface (ASPI).  It provides the following device
	  names as access to the SCSI(Small Computer Systems Interface) A system-independent expansion bus typically used to connect hard disks, tape drives, and CD-ROMs to a computer.	A host adapter connects the SCSI bus to the computer's own bus.  See also ESDI, IDE. tape, 'RMTx' (rewind on close) and
	  'NRMTx' (NO rewind on close) where x can go from 0 to 3.  There may
	  also be the following names 'MTx' and 'NMTx' which default to 1024
	  byte blocks.	The names may also have a '$' appended to try and make
	  them unique from file names of 'RMT0' etc.
	once opend these devices must be put into RAW mode
SeeAlso: AX=4402h"ASPI"


Format of ASPITAPE.SYS mtop parameter block:
Offset	Size	Description	(Table 01554)
 00h	WORD	operation code
		00h "MTWEOF" - write an end-of-file record
		01h "MTFSF" - forward space file
		02h "MTBSF" - backward space file
		03h "MTFSR" - forward space record
		04h "MTBSR" - backward space record
		05h "MTREW" - rewind
		06h "MTOFFL" - rewind and unload
		07h "MTNOP" - perform TEST UNIT READY
 02h	DWORDDoubleword; four bytes.	 Commonly used to hold a 32-bit segment:offset or selector:offset address.	repetition count


Format of ASPITAPE.SYS mtget parameter block:
Offset	Size	Description	(Table 01555)
 00h	BYTE	ASPI host ID
 01h	BYTE	SCSI(Small Computer Systems Interface) A system-independent expansion bus typically used to connect hard disks, tape drives, and CD-ROMs to a computer.	A host adapter connects the SCSI bus to the computer's own bus.  See also ESDI, IDE. target ID
 02h	BYTE	SCSI(Small Computer Systems Interface) A system-independent expansion bus typically used to connect hard disks, tape drives, and CD-ROMs to a computer.	A host adapter connects the SCSI bus to the computer's own bus.  See also ESDI, IDE. logical unit number
 03h	BYTE	device parameters
		bit 0: drive must use fixed-block read and write
		bit 7: drive is an ASPI device
 04h	BYTE	current device state (see #01556)
 05h	BYTE	unit number within driver
 06h	WORD	fixed block blocksize
 08h	BYTE	last SCSI(Small Computer Systems Interface) A system-independent expansion bus typically used to connect hard disks, tape drives, and CD-ROMs to a computer.	A host adapter connects the SCSI bus to the computer's own bus.  See also ESDI, IDE. status
 09h	BYTE	last SCSI(Small Computer Systems Interface) A system-independent expansion bus typically used to connect hard disks, tape drives, and CD-ROMs to a computer.	A host adapter connects the SCSI bus to the computer's own bus.  See also ESDI, IDE. sense key
 0Ah	WORD	last SCSI(Small Computer Systems Interface) A system-independent expansion bus typically used to connect hard disks, tape drives, and CD-ROMs to a computer.	A host adapter connects the SCSI bus to the computer's own bus.  See also ESDI, IDE. opcode (packed) (see #01557)
 0Ch	WORD	residual bytes from SCSI(Small Computer Systems Interface) A system-independent expansion bus typically used to connect hard disks, tape drives, and CD-ROMs to a computer.	A host adapter connects the SCSI bus to the computer's own bus.  See also ESDI, IDE. opcode


Bitfields for ASPITAPE.SYS current device state:
Bit(s)	Description	(Table 01556)
 0	device currently opened in buffered mode
 1	drive currently opened in nonbuffered mode
 2	rewind drive on last close
 3	drive has been written on
 4	drive has been read from
 5	next read will return 0 bytes
 6	EOM will resemble EOF
 7	drive may be busy rewinding


Bitfields for SCSI(Small Computer Systems Interface) A system-independent expansion bus typically used to connect hard disks, tape drives, and CD-ROMs to a computer.	A host adapter connects the SCSI bus to the computer's own bus.  See also ESDI, IDE. opcode:
Bit(s)	Description	(Table 01557)
 0-7	SCSI(Small Computer Systems Interface) A system-independent expansion bus typically used to connect hard disks, tape drives, and CD-ROMs to a computer.	A host adapter connects the SCSI bus to the computer's own bus.  See also ESDI, IDE. operation (SCSI(Small Computer Systems Interface) A system-independent expansion bus typically used to connect hard disks, tape drives, and CD-ROMs to a computer.	A host adapter connects the SCSI bus to the computer's own bus.  See also ESDI, IDE. packet byte 0)
 8-10	SCSI(Small Computer Systems Interface) A system-independent expansion bus typically used to connect hard disks, tape drives, and CD-ROMs to a computer.	A host adapter connects the SCSI bus to the computer's own bus.  See also ESDI, IDE. flags (SCSI(Small Computer Systems Interface) A system-independent expansion bus typically used to connect hard disks, tape drives, and CD-ROMs to a computer.	A host adapter connects the SCSI bus to the computer's own bus.  See also ESDI, IDE. packet byte 1)
 11-12	ASPI "Direction Bits" (ASPI SRB byte 3)