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Cp390 hotswap – Kontron CP390 User Manual

Page 27

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CP390

Hotswap

ID 19976, Rev. 0200

Page 4 - 5

® PEP Modular Computers GmbH

4.2.4

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.

4.2.5

Hotswap Control and Status Register / Statemachine

All hotswap peripheral boards provide a HotSwap Control And Status Register which
provides information on the current state of the board. The defined bits in this register
set are named:

Due to the fact that no 64-bit transparent PCI-to-PCI bridge currently exists, which
would provide built-in hotswap status registers, another way of implementing these bits
had to be found.

The solution, therefore, is to put this information 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 IOs).

Table 4-1: Hotswap Control and Status Register / Statemachine

Bit Name

Function

EXT

Indication of extraction process

INS

Indication of insertion process

LOO

Led on

EIM

ENUM mask bit

Table 4-2: Hotswap Register Bits

Bit Name

Signal on 21150

EXT

GPIO[2]

INS

GPIO[3]

LOO

GPIO[0]

EIM

GPIO[1]

!

Attention!

GPIO[2:3] have to be configured as inputs. A different configura-
tion may damage your bridge device.