The Fibre Channel XIO board is a half-size XIO option board that provides the high-performance interface between an Origin family system, such as an Origin2000 or Onyx2 workstation or server, and two fibre channel arbitrated loop (FC-AL or FCAL) interfaces, which are used to connect to fibre channel disk enclosures. (See Chapter 2, “Fibre Channel Basics,” for an explanation of fibre channel topology and architecture.)

The Fibre Channel XIO board is available in two versions:

The two versions have identical functionality and differ only in mechanical aspects appropriate to the platforms for which they are intended.

Each Fibre Channel XIO board has two connectors, labeled Channel 0 and Channel 1. Each channel can control up to 110 fibre channel disks. Figure 1-1 shows the Fibre Channel XIO board and connectors (version for Origin2000, Origin200, and Onyx2 servers and graphics workstations).

Board installation depends on the type of Silicon Graphics workstation or server you have.

The Fibre Channel PCI board (marketing code PCI-FC-1P, part number 9980953) is a half-size PCI option board that provides a high-performance interface between the host system and one FC-AL interface.

This board can be inserted into an Origin200 chassis, or into the PCI module of an Origin2000, Onyx2, or OCTANE chassis. The board I/O panel has one fibre channel connector, which can control up to 110 fibre channel disks. Figure 1-2 shows the Fibre Channel PCI board.

To install the fibre Channel PCI board:

LEDs on each type of Silicon Graphics Fibre Channel option board have these functions:

Each Fibre Channel XIO board has two nine-pin (DB9) female connectors; each PCI board has one such connector. Figure 1-3 shows pin assignments.

Both a copper and an optical interface are supported. The native interface is copper, as is standard for FC-AL. To use an optical cable, you must attach a media interface adapter, which is described in “Optional Media Interface Adapter (MIA)”.

You can cable a Fibre Channel XIO or PCI board to various Silicon Graphics Fibre Channel storage options. Fibre Channel enclosures can be RAID or JBOD (“just a bunch of disks”). For more information on Silicon Graphics Fibre Channel storage options, consult your Silicon Graphics sales representative or visit http://www.sgi.com/.

To support distances up to 300 meters, an optional fiber optic media interface adapter (MIA), is available; its marketing code is P-F-OE-KIT, which includes two modules (part number 9980952), one for each end of an optical cable. Silicon Graphics supports optical cabling distances of 25, 100, or 300 meters (between the host and the enclosure). The MIA is used with 62.5 μm optical cable.

The MIA uses a shortwave laser (CD-ROM laser) with a wavelength of 780 nm. A full-duplex module, it converts photons to electrons in one direction, and converts electrons to photons in the other direction.

An industry-standard duplex SC connection supplies the external fiber optic connection. This connection consists of two parts: the female part is in the MIA and the male part is on the fiber optic cable connector, as indicated in Figure 1-4. This connection is keyed.

Both types of board, XIO and PCI, provide conversion between a 1.062 gigabit fibre channel interface and a little-endian 64-bit PCI interface through the PCI-64 fibre channel ASIC. Each channel on each type of board has one of these components, as shown in Figure 1-5 and Figure 1-6, which are block diagrams of the boards.

Conversion from PCI to the 8-bit (400 MB per second) XIO interconnect link used in the Origin family of servers and graphics workstations and the OCTANE workstation is provided differently on the two boards:

Both boards support fibre channel Class 3 operations as a loop port (L_Port). The firmware supports Class 3 and FC-AL (arbitrated loop) transfers only. For details on ports, Class 3, and FC-AL, see Chapter 2.

Transceivers (SerDes) embedded on each board convert 8-bit parallel user data to 10-bit differential serial signals (8B10) and vice versa. They also provide frame synchronization, word alignment, and clock recovery for incoming serial data.

For incoming serial data, two recovered clocks at 53.125 MHz for odd or even bytes are provided as outputs on two pins, 180 degrees out of phase. Any required equalization to compensate for high-frequency losses for copper cables (by attenuating the lower frequencies to match) is supplied externally to the Fibre Channel option board. Serial data in both directions between the transformer and the external connector is AC-coupled via a capacitor.

If the Fibre Channel board loses power or the physical fibre channel connection is broken, the link that the board is attached to becomes inoperable. High-availability loop configurations require the use of a fibre channel hub (or switch).

Figure 1-5 is a Fibre Channel XIO board block diagram.

Figure 1-6 is a Fibre Channel PCI board block diagram.