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 lists the
supported codes.
Table 31:
Device control code values
2 (pin 17)
1 (pin 18)
0
0
0
0
1
0
1
0
0
1
0
1
1
1
1
1
9.6
Signal characteristics
This section describes the electrical signal characteristics of the drive's input and output signals. See Table 27
on page 70 for signal type and signal name information.
9.6.1
TTL input characteristics
Table 32 provides the TTL characteristics.
Table 32:
TTL characteristics
State
Input high
Input low
Output high (-EN Bypass A, B)
Output low (-EN Bypass A, B)
Output high (-Parallel ESI)
Output low (-Parallel ESI)
Output high (all other outputs)
Output low (all other outputs)
Cheetah 15K.6 FC Product Manual, Rev. C
0 (pin 39)
Definition
0
Reserved for power failure warning.
1
Reserved for auto negotiation of link rate.
0
Reserved.
1
Reserved.
0
Reserved.
1
4.250 GHz operation on both ports.
0
2.125 GHz operation on both ports.
1
1.0625 GHz operation on both ports.
Voltage
1.9 < V
< 5.5V
IH
-0.5V < V
< 0.9V
IL
2.4 < V
< 5.25V
OH
V
< 0.5V
OL
2.4 < V
< 0.9 V
OH
V
> 0.9V
OH
CC
0 < V
< .45V
OL
2.4 < V
< 0.9 V
OH
V
> 0.9V
OH
CC
0 < V
< .45V
OL
Current
I
= ±500nA max.
IH
I
= ±500nA max.
OL
I
< -3mA
OH
I
< 3mA
OL
I
< -2.4mA
CC
OH
I
< -500µA
OH
I
< 2.4mA
OL
I
< -1.6mA
CC
OH
I
< -500µA
OH
I
< 1.6mA
OL
75