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Intel® Server Board SE7520AF2 TPS
Functional Architecture
Revision 1.2
33
Intel order number C77866-003
restarted. This is preferred over the necessity of taking down the system, or going offline for an
extended period of time.
3.1.1.3.6
PCI Express* Hot-Plug Support
Hot-plug support is available on the PCI Express* expansion slots (Slot 3, Slot 4) on the Intel®
Server Board SE7520AF2 (SE7520HPAF2 SKU only). The PCI Express* hot-plug controller
follows the requirements and recommendations from PCI Express* Base Specification, Rev 1.0.
Three hot-plug LEDs are associated with each PCI Express* slot:
One power LED (green) on the top, adjacent to each PCI Express* slot
One attention LED (amber) on the top, adjacent to each PCI Express* slot
One attention LED (amber) on the bottom of the board, visible from the rear of the
Server Chassis SC5300
1
.
The hot-plug LEDs support three states: Off, On, or Blinking. The following table lists the
description for each state of the power and attention LEDs.
Table 1. PCI Express* Hot-Plug LED Function Table
LED
Off
On (Solid)
Blinking
Power LED
All main voltage and data
rails are removed from slot.
PCI adapter may be added or
removed
Normal power to slot. PCI
adapter may NOT be added
or removed
Slot power in transition (on-off or
off-on). PCI adapter may NOT be
added or removed
Attention LED
Normal operation
Slot on attention; power fault
or operational problem
present on the slot
Slot being identified at the user’s
request to locate the slot via the
Hot-Plug Interface Driver
3.1.1.3.7
PCI Express* Hot-Plug Controller
The PCI Express* hot-plug solution is supported via the PCA9555, a 16-bit I2C I/O expander. It
interfaces between the PCI Express* slots, hot-plug power controller, hot-plug indicators and
the MCH. The PCA9555 facilitates the hot-plug events controlled by the MCH. This includes
monitoring presence indicators from the slots, attention indicators, and fault and power good
signals. It also drives slot enables and LED indicators during hot-plug events.
3.1.1.3.8
PCI Express* Hot-Plug Power Controller
The PCI Express* hot-plug power control is supported via the MIC2591 hot-plug power
controller. The MIC2591 controller is a dual PCI Express* hot-plug power controller that
provides power control support for 12V, 3.3V and 3.3V aux. This support includes current
limiting, voltage supervision, fault indication and independent slot control. The MIC2591 also
has a programmable circuit breaker that protects against excessive loads, such as short circuit,
for each supply.
1
Requires installation of light pipe included on the Hot Plug Accessory Kit