For more information on Vitesse Products visit the Vitesse web site

at www.vitesse.com or contact Vitesse Sales at (800) VITESSE

or sales@vitesse.com

©2003 Vitesse Semiconductor Corporation

741 Calle Plano

Camarillo, CA 93012, USA

Tel: +1 805.388.3700

Fax: +1 805.987.5896

www.vitesse.com

Controller is an integrated CMOS circuit

that significantly reduces system cost by

integrating all of the digital logic typically

required to monitor a storage enclosure.

The VSC055 may be used in any embedded control application

including parallel SCSI, Fibre Channel or any other application

where the monitoring and control of a large number of digital I/O

signals is required. Programming the VSC055 is easy through a

VSC055 APPLICA TION DIAGRAM:

convenient programming model, which reduces the overall

duration of the design-in cycle. Data is read from and written to

multiple VSC055 devices on a single two-wire bus.

Furthermore, a key strength of the VSC055 is the ease in which it

interoperates with Vitesse Fibre Channel port bypass circuits

(PBC) and Enclosure Management Controllers, to provide a

complete storage control chipset.

GENERAL DESCRIPTION:

VSC055

Flash

(1M x 8 or

RS-485

xcvr

Power Supplies

& Fans

LM75

(Temp)

Flash

(1M x 8 or

512K x16)

X24C16

EEPROM

LM75

(Temp)

512K x 16)

X24C16

EEPROM

RS-485

xcvr

Drive 7

Drive 8

Drive 9

Drive 10

Drive 11

Drive 12

Drive 1

Drive 2

Drive 3

Drive 4

Drive 5

Drive 6

Drive 13

Drive 14

Local I/O (x26)

Local I/O (x26)

Arbitrated Loop A

Arbitrated Loop B

Heartbeat

DownStream

DownStream

UpStream

UpStream

DRIVE PRESENT and

FAULT LEDS

DRIVE PRESENT and

FAULT LEDS

POWER SUPPLY CONTROL,

POWER SUPPLY CONTROL,

ICMB (opt.)

ICMB (opt.)

FAN TACHS and PWM

FAN TACHS and PWM

GPIOs

GPIOs

Enclosure

Controller

Vitesse

Backplane

Controller

VSC055

Vitesse

Backplane

Controller

VSC055

Vitesse

Enclosure

Controller

VSC120

Vitesse

VSC120