XO 1.75 11089 Fix

  This page is monitored by the OLPC team.

Version Q4B05 of Open Firmware for the XO 1.75 B1 laptop had a bug (<trac>11089</trac>) which causes the laptops to boot up with a white screen if it has been ten days since their manufacture, or if the RTC battery is removed. The symptom is a white screen (nothing on it) on boot.

The Fix

Fortunately, the fix to this is simple (yet tedious):

1. Disassemble the laptop to access the motherboard (the heat spreader does not have to be removed).
2. Plug in a serial cable (see below, and a USB key with Q4B06 or later.
3. Boot the laptop. It should print out a boot sequence on the serial port, ending in Unrecognized SPI Flash ID. It should then provide an ok> prompt. If at this point, it stops somewhere else or doesn't provide a prompt (like after Releasing) you have another problem. Please contact wad.
4. Type "dir u:" to initialize the USB stack.
5. Type "flash! u:\q4b06.rom". When the laptop finishes reflashing and returns an ok>, either reboot (type "bye") or poweroff the laptop.
6. Reassemble

Finding the Serial Port

You will need an XO serial adapter. The serial port to use is UART3 (CN8). There is a chart showing the location, and this photo: