Kontron CP390 - Manual (Page 24)

CP390 Hotswap
ID 19976, Rev. 0200 Page 4 - 2 ® PEP Modular Computers GmbH
4. Hotswap
4.1 Technical Background of CompactPCI Hotswap
In many modern application systems downtime is costly and/or unacceptable. Server
applications, telecommunications networks and automated systems requiring continu-
ous monitoring call for a system design in which a single card can be inserted or
extracted without affecting the rest of the system. The ease with which a board may be
removed and replaced is dependent on the mechanical design (form factor), the possi-
bility of deactivating the software drivers for the board (operating system) and the ability
to remove and insert the board without disturbing the signal quality on the bus.
CompactPCI hotswap is currently the most effective way to meet this need. Staggered
pins on the backplane guarantee controlled power sequencing of the board, while the
signals ENUM, BDSEL, HEALTHY and the hotswap control and status register bits may
be used to control board access from the software side.
4.1.1 Hotswap System
A hotswap system consists of a hotswap platform which comprises a hotswap back-
plane, the system host (CPU) with hotswap features, cooling, power supplies etc. plus
the boards to be hotswapped. Hotswapping is not possible unless the operating system
has the capability to enable and disable the board specific driver during normal opera-
tion.