Seagate ST3146855FC ユーザーズマニュアル

Cheetah 15K.5 FC Product Manual, Rev. D

71

The drive inputs a Device Control Code on the DEV_CTRL_CODE lines at power up to determine the link rate 
on the Fibre Channel ports. Both ports run at the same rate. If the backpanel does not connect to these lines, 
the drive has 10K ohm pull up resistors that default the device control code to 7 (1.0625 GHz). Table lists the 
supported codes.

This section describes the electrical signal characteristics of the drive’s input and output signals. See Table 24 
on page 66 for signal type and signal name information.

Table 29 provides the TTL characteristics.       

2 (pin 17)

1 (pin 18)

0 (pin 39)

0

0

0

Reserved for power failure warning.

0

0

1

Reserved for auto negotiation of link rate.

0

1

0

Reserved.

0

1

1

Reserved.

1

0

0

Reserved.

1

0

1

4.250 GHz operation on both ports.

1

1

0

2.125 GHz operation on both ports.

1

1

1

1.0625 GHz operation on both ports.

Input high

1.9 < V

IH

 < 5.5V

 I

IH

 = ±500nA max.

Input low

-0.5V < V

IL

 < 0.9V

 I

OL

 = ±500nA max.

Output high (-EN Bypass A, B)

2.4 < V

OH 

< 5.25V

I

OH

 < -3mA

Output low (-EN Bypass A, B)

V

OL

 < 0.5V

I

OL

 < 3mA

Output high (-Parallel ESI)

2.4 < V

OH 

 < 0.9 V

CC

 

V

OH

 > 0.9V

CC

I

OH

 < -2.4mA

 

I

OH

 < -500µA

Output low (-Parallel ESI)

0 < V

OL

 < .45V

I

OL

 < 2.4mA

Output high (all other outputs)

2.4 < V

OH 

 < 0.9 V

CC

 

V

OH

 > 0.9V

CC

I

OH

 < -1.6mA

 

I

OH

 < -500µA

Output low (all other outputs)

0 < V

OL

 < .45V

I

OL

 < 1.6mA