Документ взят из кэша поисковой машины. Адрес оригинального документа : http://crydee.sai.msu.ru/ftproot/pub/comp/hardware/NCR/samp_code/ISA/cf9xflyr.txt Дата изменения: Tue Mar 12 00:00:00 1996 Дата индексирования: Mon Dec 24 11:44:17 2007 Кодировка: Поисковые слова: messenger

NCR 53CF94, 53CF96 FLYER INFORMATION

The NCR 53CF94 and 53CF96 Fast SCSI Controllers are high-performance CMOS
devices conforming to ANSI standards X3.131-1986 (SCSI-1) and
X3.131-199X (SCSI-2) for the Small Computer Systems Interface (SCSI).
These devices are supersets of the industry standard NCR 53C94 and 53C96,
an advanced second generation family of SCSI controllers capable of
operating in both the initiator and target roles. This family of devices
reduces protocol overhead by performing common SCSI sequences in hardware,
in response to a single command.

The NCR 53CF94 and 53CF96 feature 10 megabytes per second (MB/s) Fast
SCSI-2 data transfers, improved single-ended SCSI operation, a 24-bit
transfer counter, and enhanced SCSI-2 command functionality. They also
feature NCR TolerANT SCSI driver and receiver technology, for reliable
operation in all SCSI cabling environments. These devices are pin-compatible
with the NCR 53C94 and 53C96, offering a simple, reliable upgrade path
to Fast SCSI-2. Both are upward compatible with existing NCR 53C90 family
software.

Features and Benefits


Maximized Transfer Rates

Sustained synchronous SCSI data transfers up to 10 megabytes per second (MB/s)
Sustained asynchronous SCSI data transfers up to 7 MB/s
NCR TolerANT SCSI driver and receiver technology provides:

-Reliable data transfer in all cabling environments
-Active Negation pad cells on the SCSI Data, Parity REQ and ACK pins for
-10 MB/s Fast SCSI-2 transfers in single-ended and differential modes
-Dual ranked 24-bit transfer counter eliminates inter-sector transfer delays
and allows single transfers up to 16 MB
-DMA transfer rate up to 20 MB/s
-Programmable bus offsets (up to 15) provide improved speed matching
-Maximized Protocol Efficiency
-Host intervention minimized using combination commands to reduce host
interrupts
-Combination commands implemented with on-chip sequential logic
-Dual-ranked registers allow for command pipelining

Minimized Board Space Requirements

-On-chip 48 mA single-ended drivers and receivers
-Logic to support external differential (with 53CF96) or single-ended
transceivers

Surface mount packaging

Additional Features

-SCSI-2 compatible, implementing support for both initiator and target devices
-SCSI-2 queue tag message support with value checking
-ID Register

-Flexible bus configurations: 8- or 16-bit multiplexed and non-multiplexed
address/data bus interface
-Optional parity checking and generation for the DMA and SCSI interfaces
-Pass-through parity supported for each stage of data FIFO
-Clock frequencies from 10 Mhz to 40 Mhz are supported
-SCSI Pad performance based on more than nine years of SCSI chip design experience

Devices:
53CF94 Single-ended
53CF96 Single-ended

Packaging:
53CF94 84 pin PLCC
53CF96 100 pin PLCC


NCR Microelectronics
1635 Aeroplaza Drive
Colorado Springs, CO 80916
(719) 596-5795