9.5.12Device control codes

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.

Table 25:

Device control code values

 

 

 

 

 

 

2 (pin 17)

 

1 (pin 18)

0 (pin 39)

Definition

 

 

 

 

 

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.

 

 

 

 

 

9.6Signal characteristics

This section describes the electrical signal characteristics of the drive’s input and output signals. See Table 21 on page 60 for signal type and signal name information.

9.6.1

TTL input characteristics

 

 

Table 26 provides the TTL characteristics.

 

 

Table 26:

TTL characteristics

 

 

 

 

 

 

State

 

Voltage

Current

 

 

 

 

Input high

 

1.9 < VIH < 5.5V

IIH = ±500nA max.

 

 

 

 

Input low

 

-0.5V < VIL < 0.9V

IOL = ±500nA max.

 

 

 

Output high (-EN Bypass A, B)

2.4 < VOH < 5.25V

IOH < -3mA

 

 

 

Output low (-EN Bypass A, B)

VOL < 0.5V

IOL < 3mA

 

 

 

Output high (-Parallel ESI)

2.4 < VOH < 0.9 VCC

IOH < -2.4mA

 

 

VOH > 0.9VCC

IOH < -500µA

Output low (-Parallel ESI)

0 < VOL < .45V

IOL < 2.4mA

 

 

 

Output high (all other outputs)

2.4 < VOH < 0.9 VCC

IOH < -1.6mA

 

 

VOH > 0.9VCC

IOH < -500µA

Output low (all other outputs)

0 < VOL < .45V

IOL < 1.6mA

 

 

 

 

Savvio 10K.4 FC Product Manual, Rev. A

65

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Seagate ST9450404FC, ST9600204FC, ST300MM0026 manual Signal characteristics, Device control codes, TTL input characteristics