PORTIBM PC Portable (uses same BIOS as XT) 3518-351B - ESDI(Enhanced Small Device Interface) A disk drive interface type which was briefly popular before IDE took over.	 An ESDI drive can transfer data between the drive and controller at 10, 15, or 20 megabits per second, which is faster than an MFM or RLL controller but slower than what is possible with an IDE or SCSI drive.	 See also IDE. secondary harddisk controller
Range:	PORTIBM PC Portable (uses same BIOS as XT) 3510h-3513h (primary) or PORTIBM PC Portable (uses same BIOS as XT) 3518h-351Bh (secondary)
SeeAlso: PORTIBM PC Portable (uses same BIOS as XT) 3510h,PORTIBM PC Portable (uses same BIOS as XT) 01F0h-01F7h

3518w R-  status word
3518w -W  command word
351A  R-  basis status
351A  -W  basic control
351B  R-  interrupt status
351B  -W  attention