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2010
congatec
AG
QTOPm14
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8.1
Bootstrap Signals
Table 33
Bootstrap Signal Descriptions
Signal
Pin # Description of Bootstrap Signal
I/O
PU/PD Comment
GBE_LINK#
13
Ethernet controller 0 link indicator, active low.
O 2.5VSB
PD 1k
GBE0_LINK# is a bootstrap signal (see note below)
GBE_LINK100#
7
Ethernet controller 0 100Mbit/sec link indicator, active low.
O 2.5VSB
PU 4k99
2,5VSB
Not Supported. Internally connected to GBE_ACT#.
GBE0_LINK100# is a bootstrap signal (see note below)
GBE_LINK1000#
8
Ethernet controller 0 1000Mbit/sec link indicator, active low.
O 2.5VSB
PD 1k
Not Supported. Internally connected to GBE_LINK#
GBE0_LINK1000# is a bootstrap signal (see note below)
GBE_ACT#
14
Ethernet controller 0 activity indicator, active low.
O 2.5VSB
PU 4k99
2,5VSB
GBE0_ACT# is a bootstrap signal (see note below)
Caution
The signals listed in the table above are used as chipset configuration straps during system reset. In this condition (during reset), they are
inputs that are pulled to the correct state by either Qseven
®
internally implemented resistors or chipset internally implemented resistors that
are located on the module. No external DC loads or external pull-up or pull-down resistors should change the configuration of the signals
listed in the above table. External resistors may override the internal strap states and cause the Qseven
®
module to malfunction and/or cause
irreparable damage to the module.
Additionally, if it is necessary to have link and activity LEDs connected to GBE_LINK# and GBE_ACT# on the carrier board, then buffers must
be used since without a buffer the strapping becomes active and the PHY will be programmed to a wrong address.
