VITESSE

SEMICONDUCTOR CORPORATION

Advance Product Information

VSC7124

Quad Port Bypass Circuit

Page 2

G52293-0, Rev 2.3

5/7/01

© VITESSE SEMICONDUCTOR CORPORATION • 741 Calle Plano • Camarillo, CA 93012

Tel: (800) VITESSE • FAX: (805) 987-5896 • Email: prodinfo@vitesse.com

Internet: www.vitesse.com

Application Example

A 12-port JBOD is shown in Figure 1. This dual loop application uses one VSC7127R, one VSC7127T and one

VSC7124 on each loop in order to configure the FC-AL disk array. Functional drives are included in the FC-

AL loop while nonfunctional or missing drives (numbers 2, 7, 9) are excluded.

Figure 1: 12-Drive FC-AL JBOD Application

7125

Optics

or

Copper

SerDes

7125

SerDes

1

0

1

0

1

0

1

0

7125

SerDes

7125

SerDes

1

0

1

0

7125

SerDes

7125

SerDes

1

0

1

0

7125

SerDes

7125

SerDes

1

0

1

0

7125

SerDes

7125

SerDes

1

0

1

0

1

0

1

0

7125

SerDes

7125

SerDes

1

0

1

0

1

0

1

0

7125

SerDes

7125

SerDes

1

0

1

0

7125

SerDes

7125

SerDes

1

0

1

0

7125

SerDes

7125

SerDes

1

0

1

0

Repeater

Retimer

Retimer

Repeater

1

2

3

4

5

6

7

8

9

10

11

12

Optics

or

Copper

LOOP A

LOOP B

CONFIGURATION:

VSC7127R #1 & 2: Repeater Mode

SEL0=1, SEL5=1

VSC7127T #5 & 6: Retimer Mode

SEL1=1, SEL5=1

MODE=0

MODE=1

VSC7124 #3 & 4: No CRU

0

1

2

3

4

0

0

1

2

3

4

0

1

1

2

3

4

0