Hardware implementation
Issue C
35
Clock generation
A clock generator is used on the PROTEUS design to generate clocks required by
system components. Additional zero delay clock buffers are added as required for PCI
Express components.
Trusted platform module
The PROTEUS supports an Atmel AT97SC3203 trusted platform module (TPM), the TPM
implements version 1.2 of the Trusted Computing Group (TCG) specification for TPMs. A
Trusted Platform Module offers facilities for secure generation of cryptographic keys, the
ability to limit the use of cryptographic keys, as well as a hardware random number
generator. The TPM is interfaced via the System Management Bus (SMBUS).
Hardware monitoring and control
Circuitry is provided to monitor the PROTEUS modules voltage rails and temperatures
with application software provided to access these readings.
Intel HD Audio
The US15W SCH provides an Intel HD Audio digital interface which is made available via
the COM Express board-to-board connector. An on-board audio codec is provided on the
module in standalone mode only, this is interfaced to an onboard 2W audio amplifier for
speakers and headphone functionality. The HDA audio codec also provides support for
microphone and line in functions.
Further information on Intel High Definition Audio is available at:
The US15W SCH contains one EHCI and three UHCI USB controllers to provide support
for up six USB 2.0 ports allowing high, full and low speed USB ports and two ports
supporting high speed only operation.
USB ports 1, 3, 6 and 7 are made available on the COM Express board-to-board
connector. Port 1 is connected to USB A type connector for standalone configuration.
USB ports 6 and 7 operate as high speed only ports and as such do not support low and
full speed USB operation. Care should be taken in base board applications to ensure
these ports are only used to interface to USB high speed devices on the COM Express
carrier board and not made available externally.
Ports 0 and 2 are connected via a pin header to allow for off module expansion. Port 2
can be reconfigured in software to be a USB client port allowing the PROTEUS to appear
as a peripheral. Ports 4 and 5 are routed to the PCI Express Mini Card sockets.
