Fix Clock Using XO-1 as Communication Terminal

 

Summary

 

Is it a RTC clock problem ?

Remove the back  panel

Charge the RTC clock battery

Connect  “bricked”  XO to XO used as communication terminal

Set the RTC clock

Update software

 

Step by Step

 

Is it a RTC clock problem ?

 

  1. Check the symptoms to determine if the malfunction is the RTC problem.  The characteristic symptom is that the microphone LED flashes once, very briefly, immediately after the XO-1 is turned on and the display does not come on..  If the microphone LED stays on, there is a more serious malfunction.

 

Remove the back  panel

 

  1. Read wiki topic  Fix Clock . 
  2. Disconnect any power and remove the main battery.
  3. Remove back of  “bricked” XO by partial disassembly. 
  4. View Anna’s Video on disassembly to remove display as a guide (olpcnews forum topic XO Misc >XO for Sale by okiewan, 24 Apr 2010) .  STOP before disconnecting the display. 
  5. The four screws holding the back are about 1 ½ inch in from each corner.  The screws can be accessed by moving the display down slightly or pivoting it by lifting the bottom edge.   Do not disconnect display (i.e., not necessary). 
  6. After removing the back, replace one of the display retaining screws to keep the display in place.
  7. Assure the RTC “watch” type rechargeable battery is not loose in the computer.  The most likely situation is that the battery is just discharged, although its holder could be out of specification and not firmly hold the battery. Do not attempt to remove RTC battery if it is firmly in its socket.

 

Charge the RTC clock battery

 

  1. With the RTC battery in place, charge it by applying power and powering on the XO for several hours (even though the display does not come on). The RTC battery charges only when the XO is powered on.

 

Connect  “bricked”  XO to XO used as communication terminal

 

  1. Power off and remove power and main battery.
  2. Connect the USB to serial adapter to the internal serial port of the “bricked”. 
  3. Install the main battery. 
  4. Connect the adapter to the communication XO  containing the minicom software using the USB cable.
  5. Start the communication XO.
  6. Go to Journal and start the”mini” application.  Click on the screen and type su.  Use the up arrow to retrieve the command minicom USB0 and press Enter to run.
  7. Turn the “bricked” XO on.  The firmware commands will be echoed to the communication XO: 

                          +

                           Forthmacs

                              .

                              .

                              .

                            Init SHA-1 variables

                            Page Fault

                            ok

 

Set the RTC clock

 

  1. Use the communication XO to enter the commands to set the clock on the “bricked” XO.
  2. Power off the now repaired XO by holding in its power button.
  3.  Shutdown the communication XO.  Disconnect the USB cable. 
  4. Remove the main battery from the repaired XO. 
  5. Remove the serial cable from the repaired XO.
  6. Reinstall the main battery on the repaired XO.  It should now boot normally.

 

Update software

 

  1. Update the buggy firmware (or entire  firmware / software) as soon as practical.