The ESM technology(Embedded System Module) is a flexible standard for plug-on modules for industrial computers. The ESM modules help to reduce costs because the complete embedded system with processor and chipset, memory and input/output are located on the module and there are expansion options via the PCI bus.
The system-on-module( SoM) concept significantly shortens development times. ESM modules can be implemented on different carrier boards - euroboards or individual single- board solutions - as well as on Windows or Linux platforms. The specifications for ESM modules include the mechanical and electrical as well as the temperature-dependent data. As CPU platform the well-known processors from Intel, AMD, IBM or Hewlett Packard are used. The PCI bus and PCI-X bus are used as bus concepts.
Functionally, there are no limits to the ESM board. It ranges from a simple passive carrier board to a complex computer module. Only the mechanical specifications, dimensions and system connectors are standardized. The ESM module format is 71 mm x 149 mm, whereby the board depth, the insertion depth of a euroboard uses. On the front side, 63 mm are reserved for the I/O connector, although these are not defined. So an ESM module can be equipped with RJ45 connectors or with Sub-D connectors. The system connection is made via the PCI bus.