Kontron CP690HS, Руководство пользователя

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Hot Swap CP690HS
Page 5 - 6 ID 20955, Rev. 05
P R E L I M I N A R Y
5.2 Design Implementation on CP690HS
5.2.1 Power Ramping
On the CP690HS, a special hot swap controller is used to ramp up the supply voltage of the
PMC modules (Back-End Power). This is done to avoid transients on the 3.3V and the 5V pow-
er supplies from the hot swap system. When the power supply is stable, the hot swap controller
generates a reset on the PMC slots to put the devices into a definite state.
5.2.2 Precharge
Precharge is provided on the CP690HS by a resistor on each signal line (PCI bus), connected
to a 1V reference voltage.
5.2.3 Handle Switch
A microswitch is situated in the extractor handle. Opening the handle initiates the generation
of the ENUM interrupt (produced by the onboard logic).
5.2.4 ENUM# Interrupt
The onboard logic generates a low active interrupt signal to indicate that the board is about to
be extracted from the system or inserted into the system.
5.2.5 Hot Swap Control and Status Register/Statemachine
All hot swap peripheral boards provide a Hot Swap Control and Status Register which provides
information on the current state of the board. The defined bits in this register set are named, as
follows:
These bits are implemented into the onboard logic. Since on-chip registers handle read and
write accesses in the same way, it is necessary to exercise care when configuring the
PCI-to-PCI GPIOs (General Purpose I/Os).
Table 5-1: Hot Swap Control and Status Register / Statemachine
BIT FUNCTION
EXT Indication of extraction process
INS Indication of insertion process
LOO Led on
EIM ENUM mask bit