COM Express Compact Module features Integrated Condition Monitoring

Embedded PCs have increasingly found common use in recent years. Their applications range from simple data acquisition to complex control systems. Together with this comes a growing complexity of the application, requiring extensive flexibility of the hardware. To meet this demand for flexibility, small form factor Computer-On-Module (COM) are often used, which reduce the complexity of modern processors and chipsets by using standardized interfaces.

With the Toucan-TC, LiPPERT Embedded Computers offers a module in the well-known COM Express Compact form factor, whose low power consumption makes it ideal for battery-powered, mobile applications. The other features of the module -CAN bus interface and condition monitoring- are unique for standard Computer-On-Modules.

The low power consumption is achieved through the use of the Intel Atom processor E6xxT; this CPU, together with the chipset has a specified thermal design power (TDP) of only about 3 watts. It doesn’t require a North Bridge or an external graphics unit. Both are already integrated in the CPU. The corresponding EG20T Platform Controller Hub contains all the embedded-range standard interfaces such as LAN, USB, Serial, CAN, SATA and other I/O.

The two-chip solution allows the integration on a small, only 95 mm x 95 mm measuring COM Express Compact Module. Because the COM Express specification defines no connectors for the CAN bus or serial interfaces, the Toucan-TC places these on a lockable option-connector. Thus, a mechanically stable arrangement of can be achieved.

Embedded computer systems are often used in stand-alone systems that must operate reliably for long periods. For this they are constantly observed — their loss can usually not be tolerated. To monitor their operational state, so-called condition monitoring is used. With condition monitoring, the module’s key parameters can be proactively observed and, when required, preventive maintenance can be initiated.

Condition monitoring includes not only the current operating state, but also historical records of past conditions. The ambient temperature may serve as an example: whether it exceeded or fell below the permissible limits is an essential criterion for the electronics’ expected life time.

It is also desirable to know the actual current consumption of the system. With this, one can make statements about the system’s state, which are well above a simple "Go / No go” statement.

When doing error analysis, not only records of the environmental conditions are important, but also details of the up-time, or of any previous errors that have resulted in the restart of the system. It is also interesting to know the entire accumulated run time of the system. Thus, its remaining service life can be estimated easily.

The Toucan-TC has built in support for all these functions, the LiPPERT Embedded Management Technology (LEMT). The LEMT functions are implemented within the in System Management Controller (SMC), a micro controller, which is necessary anyway. It communicates via the SM bus with the COM module’s chipset. The SMC has built-in flash and RAM areas, which LEMT functions make available. The flash area is divided in manufacturer and user specific part. The manufacturer part is used to store pertinent information about the device, such as part number, BIOS revision and the like. The 1 kB user flash is available for persistent data of the application. Additionally, there is a 128 byte one-time-programmable region of flash memory for critical data like security keys that may not be changed.

All these features are accessed using the provided user interface program. However, LEMT functionality can also be integrated into the user’s application. A source code interface is available, providing access to LEMT’s functions.

One last feature worth mentioning is the Fail-Safe-BIOS. If an update fails due to a power failure during the process, the board can’t be accessed any longer. The secondary BIOS automatically takes over when the first one is corrupted.

A white paper with detailed description of LEMT functions and implementation is available on LiPPERT’s website.

LiPPERT Embedded Computers, Inc.
5555 Glenridge Connector
Suite 200
Atlanta, GA, 30342

tele: 404.459.2870
fax: 404.459.2871