Flat Cable Interface; Vmebus Interface - Silicon Graphics POWER CHALLENGE User Manual

Chapter 1: Introducing the Challenge Deskside Servers
6

Flat Cable Interface

The IO4 contains two FCI interfaces that are proprietary to Silicon Graphics.
FCIs are synchronous, point-to-point interfaces that allow communication
between devices connected by a cable. The FCI is used to connect to the
VME64 bus adapter. FCIs can operate at up to 200 MB per second for
VMEbus adapters.
The FCI on the first IO4 in a system is connected to the VME Channel
Adapter Module (VCAM) board, which contains a VME adapter subsystem
in the backplane.
POWER Challenge systems using the visualization console option have a
Graphics Channel Adapter Module (GCAM) board. The GCAM contains a
VME adapter subsystem and interfaces to the optional visualization console
graphics board in the fifth VME slot. An FCI interface is routed to a
connector on the front of the optional GCAM.
Note that the optional visualization console graphics board uses VME slots
3, 4, and 5 when installed. This leaves two VME slots available for use.

VMEbus Interface

The VMEbus is supported through a VCAM interface (GCAM with the
visualization console option) connected to an IO4 board. This bus is
standard equipment and is located in the main backplane, next to the Ebus.
The VCAM or optional GCAM plugs directly into the IO4 board without any
cabling.
The VME interface supports all protocols defined in Revision C of the VME
Specification, plus the A64 and D64 modes defined in Revision D. The D64
mode allows DMA bandwidths of up to 60 MB per second. The VME
interface can operate as either a master or a slave. It supports DMA to
memory on the Ebus and programmed I/O operations from the Ebus to
addresses on the VMEbus.
In addition to interfacing with the VMEbus, the VCAM or optional GCAM
provides scatter/gather virtual address translation capability and a DMA
engine that can be used to increase the performance of non-DMA VME
boards. See Appendix E for additional VME information.