2192-12132-000-000
CompactFlash
The power supply to the CompactFlash interface is controlled via software, and supports hot
swap card insertion and CompactFlash power down states. GP82 on the PXA255 is used to
control the power supply, setting this line low (logic 0) will switch off power to the CompactFlash
interface.
Ethernet
The network interface supports a power down mode, which shuts down the internal MAC and
PHY blocks of the network controller. Placing the controller into low power mode can reduce the
power consumption of the VIPER by up to 700mW.
USB
The USB Host controller supports a power down mode. Placing the controller into power down
mode can reduce the power consumption of the VIPER by up to 130mW.
Audio
The Audio interface supports the AC ’97 Low Power Modes, shutting down the digital interface
can reduce consumption by up to 45mW and shutting down the analog interface can reduce
consumption by 100mW.
Status LED’s
There is a single status LED on the VIPER. This indicates Flash access, accessing either the
boot device or the main Flash array will result in the LED flashing.
RESET Switch
A momentary switch (Push to Make) may be connected on LK1. If the switch is pressed it will
cause the board to be reset. All onboard devices will be reinitialised. This may be useful during
development to restart the board after a software crash.
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