Here is an example of using a second XO. Does this help ?
I fixed several "bricked" XO's caused by the loose RTC battery using a Sparkfun (sparkfun.com) USB to serial breakout board BOB-00718 ($15) and a three wire null modem cable to the XO (TX to RX; RX to TX; ground to ground; do not connect 3.3 volt -- supplied by USB port). The cable connector was a copper foil (tape) pattern on a piece of plastic and was wedged under the pins of the connector of the XO. An alternative is copper wires imbedded in epoxy glue and filed flat with a hobby file. Also needed is a USB A to USB mini 5 pin cable ($4).
A second, working XO was used as the terminal via the USB port (any). The terminal software was minicom obtained by "YUM install minicom" (as su ) and configured using minicom -s per: http://wiki.laptop.org/go/Fix_Clock
An additional configuration step was to change the flow control to software YES and hardware NO.
The pinouts of the XO serial port are given in: http://wiki.laptop.org/go/Serial_adapters
The lower pin (white dot at back of connector) is pin 1 (3.3 volts -- unused). Pin 4 at the top is ground. Pin 2 is TX and pin 3 is RX. As a safety factor, remove the main battery of the "bricked" XO before connecting or disconnecting its cable.
Start the XO used as the terminal and run the Terminal Activity and then: su and then with: minicom USB0 . Start the "bricked" XO and a list of options will appear on the terminal with the last two lines of "Page fault" and "ok" .
Enter the commands and date / time values given in the Fix Clock article. Example line (ss mm hh dd hh mm yyyy set-time):
ok select /rtc
ok 01 30 13 31 01 2010 set-time
A 01 in the month field (all others 00 or 0000) is sufficent to allow booting. The actual values can be used or the date command used later on the fixed XO. Ignore the date / time error fault message if you use only the month.
Power down the fixed XO with the power switch, shutdown the XO terminal, and remove the cable from the fixed XO. Power the fixed XO on and it will try to find a boot device and then boot.
As a side bar, the driver ttyUSB0 in /dev is recreated each time the XO terminal is started. IF the device is not present and working (in my case, connected 3.3 volt pin on serial port, in error) the driver will not appear. Also, the device should appear as fdti_sio in the list of devices displayed by the command: lsmod .
Finally, The RTC battery is a rechargeable battery and is recharged ONLY when the XO is powered on. So, if the battery may be discharged, leave the XO powered on for several hours, even though it does not boot. Its voltage is 2.5 to 2.7 volts during most of its discharge cycle. CAUTION: the battery holder is glued with a weak glue. If you must remove the battery (not recommended), firmly hold down the holder and use a twisting motion (not prying) of a screwdriver between the holder and the battery to remove the battery.