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10.25 pc 11.25 pc

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34.5 pc

LSIU160. This oscillator provides the clock frequency necessary to support Ultra160 SCSI transfers of up to 160 Mbytes/s.

1.3.3SCSI Bus Activity LED Connector

A SCSI Bus Activity LED connector indicates the status of the SCSI bus when a LED is attached. This LED lights when the SCSI bus is transferring information.

1.4Benefits of Ultra160 SCSI

 

Ultra160 SCSI delivers data up to two times faster than Ultra2 SCSI.

 

Ultra160 SCSI is an extension of the SPI-3 draft standard that allows

 

faster synchronous SCSI data transfer rates than Ultra2 SCSI. When

 

enabled, Ultra160 SCSI performs 80 megatransfers per second resulting

 

in approximately double the synchronous data transfer rates of Ultra2

 

SCSI. The LSI53C1010 performs 16-bit, Ultra160 SCSI synchronous

 

data transfers as fast as 160 Mbytes/s. This advantage is most

 

noticeable in heavily loaded systems or large block size applications

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such as video on-demand and image processing.

 

The Ultra160 data transfer speed is accomplished using DT clocking. DT

 

clocking refers to transferring data on both polarity edges of the request

 

or acknowledge signals. Data is clocked on both rising and falling edges

 

of the request and acknowledge signals. Double-edge clocking doubles

 

data transfer speeds without increasing the clock rate.

1.4.1Cyclic Redundancy Check (CRC)

Ultra160 SCSI includes CRC which offers higher levels of data reliability by ensuring complete integrity of transferred data. CRC is a 32-bit scheme, referred to as CRC-32. CRC is guaranteed to detect all single bit errors, any two bits in error, or any combination of errors within a single 32-bit range.

1.4.2Asynchronous Information Protection (AIP)

AIP is also supported by the LSI53C1010, protecting all non-data phases, including command, status, and messages. CRC, along with AIP, provides end-to-end protection of the SCSI I/O.

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Using the LSIU160