XO 1.5 USB Keyboard

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This page describes how to change the keyboard in a XO-1.5 Laptop to a non-membrane USB version.

Scope

These are detailed instructions for installing a non-membrane keyboard into an XO-1.5 laptop. They apply to all pre-production as well as production models. With little change, they also apply to the later model of the XO-1 (with a single capacitive touchpad).

Credit is freely given to the author of the instructions for doing this modification to an XO-1 (part I, II), found on instructables.com.

WARNING

This modification includes permanent modifications of the XO laptop, and cannot be reversed. Even if you are experienced, there is a significant chance of damaging the laptop beyond repair while following these instructions.

Material

You will need:

  • An XO-1 (CL1A) or XO-1.5 (CL1B) laptop
  • A micro USB keyboard (such as this one).
    micro USB Keyboard
  • A #1 screwdriver
  • Fine pitch soldering equipment
  • A magnifier of some sort (lens, loupe, microscope...)
  • An X-Acto knife
  • A small file and/or fine grade sandpaper
  • A way of cutting steel and grinding plastic (such as a Dremel tool)
  • cellulose (scotch) or polymide (kapton, preferred) tape
  • quick drying epoxy glue or archival double-sided tape

Instructions

Preparing the Keyboard

Test the new USB keyboard by plugging it into the XO and typing on it.
Screw locations in USB keyboard
Open up the USB keyboard.
USB keyboard and its KBC
Separate the keyboard controller (KBC) from the keyboard by gently pulling on the FPC.
USB keyboard and its KBC
Top of USB KBC Remove (unsolder) the LEDs and the crystal.
Clip the pins on the board bottom.
Bottom of USB KBC
Move the crystal to the edge of the board, extending its leads with 28ga solid wire. Be careful that you don't pull the pads off the PCB and break the traces. The copper plating is very thin!
Crystal after moving
Insulate the crystal using cellulose or polymide tape, to prevent its case from shorting, or being shorted to, other circuits in the area. Remove the stress relief and first 25cm of insulation (leave USB A end on cable for testing, for now).
Modified USB KBC board
Remove the plastic tabs at the top of the keyboard.
Keyboard tabs
Reattach the keyboard to the USB KBC, and retest for full functionality.

Dismantling the XO

Make sure the laptop is running the latest firmware: q2e41 for XO-1 and q3a35 for XO-1.5.
Remove the hinge cover (link to disass. guide).
Remove the handle cover (link to disass. guide).
Disconnect the top and bottom halves of the XO, setting the top unit aside for now (link to disass. guide).
Completely disassemble the bottom half (leaving only the FPC cable connected to the touchpad --- that connector is incredibly fragile and easy to break.) (link to disass. guide, except missing).
Upper base assembly disassembly
Remove the keyboard and XO KBC board.
Keyboard Controller (w. foam)
Base Assembly Components Remove the waterproofing foam and rubber covering from the KBC controller. Save the rubber.
Keyboard Controller PCB

Modifying the Keyboard Tray

Remove any cable glue residue from the bottom of the keyboard.

   XO Keyboard

Remove the keyboard membrane and two circuit layers.

   XO Keyboard wo. silicon

Cut the keyboard plate as indicated.

   Keyboard Plate Cuts
   Resulting Pieces

Please grind down the edges of the cut metal to avoid personal injury. It is necessary along the edge of the keyboard tray to avoid damaging the keyboard FPC. Bend the top tab of the keyboard tray. Color the sides of the keyboard tray for vanity's sake (w. marker or paint).

   [[Image:XO1.5_USBKB_Photo14.jpg|100px|Prepared keyboard tray]

Remove the spacing flanges from the side bumpers

  <photo of the side bumpers with the flanges>
  <photo of the side bumpers after removing the flanges>

Hooking up the Touchpad

Reassembling the XO