APOLLO Technical Manual
Jumpers and connectors
USR1 – User-defined jumper 1
This jumper is user-configurable and can be used by an application program to signify a
configuration setting. The status of this jumper is read through the firmware hub general
purpose inputs, located at memory location FFBC0100H bit 1. This is an 8-bit read and
a read-only memory location; writing to this bit has no effect.
USR1
Description
Bit is low ‘0’.
Bit is high ‘1’.
Default setting:
USR2 – User-defined jumper 2
This jumper is user-configurable and can be used by an application program to signify a
configuration setting. The status of this jumper is read through the firmware hub general
purpose inputs, located at memory location FFBC0100H bit 2. This is an 8-bit read and
a read-only memory location; writing to this bit has no effect.
USR2
Description
Bit is low ‘0’.
Bit is high ‘1’.
Default setting:
CMOS reset
Used to clear the contents of the battery backed CMOS memory.
Changes to this jumper setting must only be made with board power completely
removed. To do this you must remove the power cable.
CMOS
Description
Reset CMOS memory.
CMOS unchanged.
Default setting:
© 2005 Arcom Issue A
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