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PRODUCT MANUAL EPX-C380
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The EPX-C380 supports either AT (standard power supply) or ATX type power supplies. Zero load supplies are
recommended.
JP2
specifies the style of supply connected to the single board computer (SBC). An AT power supply is a
simple on/off supply with no interaction with the single board computer. Most embedded systems use this type of power
supply and it is the default setting.
ATX type power supplies function with a “soft” on/off power button and a +5 VSB (standby). If an ATX compatible power
supply is connected,
JP2
should be set accordingly and a power button (momentary contact) connected between pin 3
(power button) and pin 2 (ground) of
J8
. The +5 VSB signal provides the standby voltage to the EPX-C380 but does not
power any other features of the board. When the power button is pressed, the EPX-C380 pulls PSON (Power Supply On)
low and the power supply turns on all voltages to the single board computer. When the power button is pressed again,
the BIOS signals the event so ACPI-compliant operating systems can be shutdown before the power is turned off. In ATX
mode, if the power button is held for 4 seconds, the power supply is forced off, regardless of ACPI. Since this is software
driven, it is possible that a software lockup could prevent the power button from functioning properly. For the BIOS to
report the ATX supply to ACPI-compatible operating systems,
JP2
must be setup correctly.
JP2 - Power Supply Selection
Visual
Index
AT Power
1-2, 3-4, 5-6, 7-8 (default)
ATX Power
1 2, 3 4, 5 6, 7 8
□ □
□ □
□ □
□ □
2
4
6
8
JP2
1
3
5
7
Preliminary
