Sun Microsystems 220R - Manual (Page 254)

C.1.2.1 U2P ASIC
The UPT-to-PCI bridge (U2P) ASIC controls the PCI buses. It forms the bridge from
the UPA bus to the PCI buses. For a brief description of the U2P ASIC, see Section
C.1.12 “ASICs” on page 271.
C.1.2.2 Symbios 53C876 SCSI Controller
The Symbios 53C876 SCSI controller provides electrical connection between the main
logic board and the internal and external SCSI buses to the PCI bus. The Symbios
controller is two SCSI controllers on the same PCI slot. Controller “A” is used to
interface to internal devices. The second controller, controller “B,” is used to interface
to external devices.
C.1.2.3 PCIO ASIC
The PCI-to-EBus/Ethernet controller (PCIO) ASIC bridges the PCI bus to the EBus,
enabling communication between the PCI bus and all miscellaneous I/O functions,
as well as the connection to slower on-board functions. The PCIO ASIC also embeds
the Ethernet controller.
C.1.3 UltraSPARC II Processor
The UltraSPARC II processor is a high-performance, highly-integrated superscalar
processor implementing the SPARC-V9 64-bit RISC architecture. The UltraSPARC II
processor is capable of sustaining the execution of up to four instructions per cycle
even in the presence of conditional branches and cache misses. This sustained
performance is supported by a decoupled prefetch and dispatch unit with instruction
buffer.
The UltraSPARC II processor supports both 2D and 3D graphics, as well as image
processing, video compression and decompression, and video effects through the
sophisticated visual instruction set (VIS). VIS provides high levels of multimedia
performance, including real-time video compression/decompression and two streams
of MPEG-2 decompression at full broadcast quality with no additional hardware
support. The UltraSPARC II processor provides a 2-Mbyte ecache, with an 300-MHz
operating frequency.
UltraSPARC II processor characteristics and associated features include:
4 SPARC-V9 architecture compliant
4 Binary compatible with all SPARC application code
4 Multimedia capable visual instruction set (VIS)
4 Multiprocessing support
254 Sun Enterprise 220R Server Service Manual
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January 2000, Revision A