鈩?/div>
SINGLE-CHIP PCI-SCSI CONTROLLER
BENEFITS
鈥?Builds upon proven SCSI
technology 鈥?a drop-in
replacement for the wide SCSI
industry standard LSI53C825
鈥?Reduces PCI bandwidth
requirements for execution of
I/O operations
鈥?Provides new features for
OVERVIEW
The LSI53C825AE controller is a cost effective I/O solution for host
adapter, workstation and server designs. A drop-in replacement for the
LSI53C825, the LSI53C825AE features performance upgrades and performs
fast and wide SCSI synchronous data transfers at up to 20 MBps in single-
ended or differential modes. The device improves SCSI system performance
by reducing the PCI bandwidth required to perform I/O operations. It is designed
to connect gluelessly to the Peripheral Component Interconnect (PCI) bus,
and supports PCI extended access cycles, enabling the system architect to
take advantage of PCI鈥檚 performance potential. The LSI53C825AE provides
full SCSI-2 capabilities, and features LSI Logic鈥檚 TolerANT SCSI driver and
receiver technology for reliable operation in all cabling environments.
廬
enhanced PCI performance
and flexibility
FEATURES
鈥?Performs wide high-speed SCSI
bus transfers in single-ended
and differential mode up to:
鈥?20 MBps synchronous
鈥?7 MBps asynchronous
鈥?SCRIPTS Instruction Prefetch
鈥?536-bytes buffer allows burst
length of up to 128 transfers
鈥?Load and Store instruction
鈥?4 KB static RAM for SCRIPTS
instruction storage
鈥?32 additional scratchpad
registers for user-defined functions
The LSI53C825AE and the Storage Device Management System
(SDMS
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) software comprise a complete PCI to SCSI solution. LSI Logic鈥檚
SCSI SCRIPTS鈩?software tools are also available for programming the
customized SCSI software applications.
Performance-enhancing features on the LSI53C825AE include a 4 KB
internal static RAM for SCRIPTS instruction storage which allows tailored
SCSI sequences to be executed locally鈥攕aving the PCI bus bandwidth for
other system tasks. A 536-byte DMA FIFO increases system performance by
allowing burst lengths of up to 128 transfers. Other PCI performance-
enhancing features include:
鈥?SCRIPTS instruction prefetch, permitting fetching of four or eight double
words of instructions or instruction operands
鈥?Support for PCI extended access cycles: Memory Read Multiple, Memory
Read Line, and Memory Write and Invalidate
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