The Softer Side of Hot-Swap
Summary
For years, developers have used proprietary technology to create hot-swappable applications, allowing users to remove, replace and upgrade hardware and software in run-time without lapses in system availability. While CompactPCI is a key component of the "Plug and Play" concept and has taken the lead in creating a standard solution that supports hardware run-time swapping, significant challenges remain on the software side. For example, when swapping boards and switching original executing software to an upgraded version, the transaction must take place without disrupting the applications duties and timing requirements. On the hardware side, special circuitry (hot plug connectors) must be developed so that a board can be inserted and removed from a live, operating PCI bus. The Link Handler allows interprocess communication to happen in the same manner whether the application uses a single CPU or a vast number of CPUs distributed throughout a system.