MEN Micro says its new format is poised to be designated as an American National Standards Institute (ANSI) standard by the
VME Industry Trade Association (VITA), and will be dubbed ANSI-VITA 59 RSE (rugged system-on-module express). The design of the 4.9 x 3.75 inch modules had the following goals, according to the company:
- Power dissipation of up to 35 watts
- Cooling by both conduction and convection
- An open processor architecture
- Extreme resistance against shock and vibration
To achieve these goals, ESMexpress modules are screwed into a frame (below) and then optionally enclosed in an aluminum housing. The high pressure caused by the screw joints between the housing and the PCB supports the thermal connection of the components. If additional cooling is required, the housing can be connected to a heat sink or other external heat dissipation system; at the same time, the housing ensures optimal EMC (electromagnetic compatibility) protection for the electronic parts, says MEN Micro.

The ESMexpress modules are screwed tightly into a frame
(Click to enlarge)The electrical signals from the module are distributed on one or two 120-pin connectors, depending on the required functionality. ESMexpress provides four single-lane PCI Express ports and one port which can be configured as one x16, one x8, two x4, or two x1 ports. Additionally possible are three gigabit Ethernet ports, eight USB, three SATA, SDVO, LVDS, HD audio, several utility signals, and a single 12V power supply. Pin assignments are fixed, in order to guarantee the interchangeability of the ESMexpress modules.
According to MEN Micro, ESMexpress can also be made compatible with COM Express, via the company's AE12 carrier adapter. This product adapts both mechanics and pinouts so that ESMexpress modules can be used on COM Express carrier boards. Similarly, future adapters could be created that adapt COM Express modules to ESMexpress carrier boards, the company says.

The ATX-format XCI carrier boardAn initial example of a ESMexpress carrier board is MEN Micro's ATX-format XCI. As illustrated by the photo above, it includes an ESMexpress slot, eight PCI Express slots, DVI video output, HD audio, and three SATA interfaces. Three "real-world" ports for gigabit Ethernet and six ports for USB 2.0 are also included.
ESMexpress modulesAn ESMexpress module can employ any processor architecture, says MEN Micro, as long as the maximum power dissipation of 35W is not exceeded. Two modules have been released initially: the
Intel Atom-based XM1, and the Power PC-based XM50. Both will run Linux, VXWorks, and QNX, but, of course, the only one to be compatible with Windows is the x86-compatible XM1.

The Intel Atom-based XM1 processor module
(Click to enlarge)The XM1, pictured above, includes the 1.1GHz Atom Z510 or 1.6GHz Z530 processor, along with the expected US15W SCH (system controller hub). It has up to 1GB of soldered DDR2 memory, locked to the frontside bus frequency of either 400MHz or 533MHz.
The module has a full-load power consumption of just 5.7 watts and operates over a temperature range of -40 to 85 deg. C, according to MEN Micro. It includes a covered frame, on top of which a heat sink can be placed. The module can also be used without the frame and cover if operating temperatures are sufficiently moderate.
Interfaces on the XM1 are all relayed to the outside world via the ESMexpress connectors, and include:
- 1 x SATA
- SDVO and LVDS graphics, with maximum resolution of 1368 x 768 pixels
- 8 x USB host ports, or 7 x USB host and 1 x USB client
- 1 x gigabit Ethernet
- 1 x GPIO line for LED
- HD audio
- One x1 PCI Express lane
Confirming the shock tolerance of the ESMexpress design, the XM1 is rated to withstand shocks of 15G for 11ms, bumps of 10G for 16ms, or sinusoidal vibration of up to 1G between 10 and 150Hz.
Further informationFurther information on ESMexpress or the Power PC-based XM50 can be obtained from the MEN Micro website,
here. Pricing for the XM1 starts at $567, according to the company.
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