ATAPI

6/13/98

ATAPI (ATA Packet Interface). ATAPI is a technology to use CDROM drives and cartridge tapes on the IDE (AT Attachment) interface normally used to connect inexpensive hard drives to PCs. ATA/IDE is noted for it's low cost and relatively high performance -- giving performance approaching that of SCSI at substantially lower cost. ATA can support bursts of 3.3 to 16 MByte/second depending on the PIO rate. This is about 20% less than SCSI. Sustained rates may be 20% or more less than the burst rate.

ATAPI extends the ATA/IDE disk interface to support packets which can share the bus with hard drives. ATAPI replaced a collection of proprietary interfaces. Although ATAPI is compatible with IDE electronics, some pre-1996 IDE controllers/BIOSes can not recognize an ATAPI device. As a rule of thumb, most BIOSes that support LBA/CHS for disk drives also support ATAPI. Some other BIOSes may work. For example, AMI BIOSes as early as July 1994 are reported to support ATAPI.

ATAPI is an ANSI standard supported by the X3T13 committee.

Web Reference:

ftp://fission.dt.wdc.com/pub/standards/x3t13/x3t13.htm