Seagate Cheetah 10K.6 FC ST336607FC, Product Manual

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60 Cheetah 10K.6 FC Product Manual, Rev. F
9.5.12 Device 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 24 lists the
supported codes.
9.6 Signal characteristics
This section describes the electrical signal characteristics of the drive’s input and output signals. See Table 20
on page 55 for signal type and signal name information.
9.6.1 TTL input characteristics
Table 25 provides the TTL characteristics.
9.6.2 LED driver signals
Fault and Active LED signals are located in the FC-SCA connector (J1) and through the indicator connector
(J6). See Table 26 for the output characteristics of the LED drive signals.
Table 24: 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 Reserved.
1 1 0 2.125 GHz operation on both ports.
1 1 1 1.0625 GHz operation on both ports.
Table 25: TTL characteristics
State Voltage Current
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
Table 26: LED drive signal
State Current drive available Output voltage
LED off, high 0 < I
OH
< 100µA
LED on, low I
OL
< -30 mA 0 < V
OL
< 0.8V