ARTICLE POSTED September 2nd, 2002 INCITS launches work on BIOS interface to access mass storage devices By Kathleen McMillan At its August 20-22 meeting, Technical Committee T13 of the InterNational Committee for Information Technology Standards (INCITS) was scheduled to begin work on the BIOS Enhanced Disk Drive Services 3 (EDD-3) standard. EDD-3 builds on EDD-2 to address new storage technologies to provide a BIOS interface that operating systems can use to access ATA/ATAPI, SCSI, Fibre Channel, 1394, InfiniBand, PCI Express, USB, Serial ATA and other buses to which disk drives can be attached. INCITS is the venue of choice for information technology developers, producers and users for the creation and maintenance of formal IT standards. INCITS is accredited by, and operates under rules approved by, the American National Standards Institute (ANSI). These rules are designed to ensure that voluntary standards are developed by the consensus of directly and materially affected interests. A little background T13 first undertook the Enhanced Disk Drive program in 1995 to document industry practices on how to boot a system. Hard drives were getting larger and larger, and as a result, systems were not able to boot easily. If a hard drive had over 528MB, the BIOS in an x86 architecture machine could not recognize it. Curtis Stevens, who was then with Phoenix Technologies and is now director of software engineering with Pacific Digital Corp., broke the 528MB barrier, and EDD-1 was born. EDD-2 made it possible for system firmware to report on myriad drives. Before that, adding a drive could cause the system to stop booting. With this iteration of the Enhanced Disk Drive specification, the BIOS could go out and scan boot devices to find out what it could control, recognizing the difference between a master and slave device. This ability was predicated on the fact that each device has a unique number assigned to it. EDD-2 provided a way to return the unique number of a device, thereby recognizing it. While T13 was developing EDD-2, Intel was working on PCI Express, and AMD was working on HyperTransport. Neither had emerged commercially by the time EDD-2 premiered, however. In addition to the technologies covered by EDD-2, EDD-3 will also address InfiniBand, 3GIO, CD-ROM Boot and INT Functions 0-39th. A mature specification Stevens, who first proposed the EDD-3 project to T13 in April 2002, brings a mature specification to this standards development effort. (This is happening more and more in the INCITS arena to enable the program of voluntary standards development to keep pace with the industry.) EDD-3 builds in the El Torito specification to enable bootable CDs. El Torito, which Stevens worked on while at Phoenix Technologies, had been a Phoenix Technologies-IBM document that was publicly available on the Web. In summary, important features of the proposed EDD-3 BIOS interface include: Accessing devices where the host has up to 64 bits of address space and the device has more than 28 bits of address space. Providing data read and write capability. Documentation for cylinder-head-sector (CHS) BIOS interfaces. Documentation for logical-block address (LBA) BIOS interfaces. Support for ATA and ATAPI on several host buses. Developers of this new standard may identify other interface requirements in addition to those already covered. This is a compelling reason for any company or individual with a material interest in new storage devices to join T13 and help shape the standard. Details about T13's meeting schedule are at www.incits.org/tc_home/t13.htm. Maxtor Corp. was slated to host the August meeting near its headquarters in Longmont, CO. Calls for patents As is customary with all projects developed under the rules of ANSI, which accredits INCITS, T13 will make regular calls for patents at meetings addressing the technical report. The officers of INCITS' Technical Committees make a concerted effort to ensure that the American National Standards resulting from their work are unencumbered by costly assertions of intellectual property rights. The target date for initial public review of EDD-3 is February 2003. Stevens' involvement in the standards development process will continue with his services to T13 as group secretary and editor of the EDD-3 document. Maxtor's Pete McLean serves as Chairman of T13. Contact information: INCITS Secretariat, Information Technology Industry Council (ITIC), 1250 Eye St. NW, Suite 200, Washington, DC 20005 (www.incits.org). About the author Kathleen McMillan is senior director of the Secretariat for the InterNational Committee for Information Technology Standards (INCITS). Feedback: feedback@snwonline.com Questions: questions@snwonline.com Technical difficulties: webmaster@snwonline.com