SPI FLASH Recovery/XO-1.5

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(to be merged with SPI_FLASH_Recovery_for_XO-1.5)

Contents

You Need

  • the bricked laptop, called the target,
  • a working XO-1.5 laptop, with latest Firmware, and a serial cable, called the host,
  • a third computer to act as a terminal to the host, a serial cable, with serial port configured for 115200 bps,
  • wire, soldering iron, antistatic environment,
  • optional IDC 2.54mm six pin through-hole DIL headers, and an IDC cable 15cm long,

Setup

  • remove main battery and power cords from target and host laptops,
  • disassemble the target and host to flip PCBs and lay them out with top edges close but not touching,
  • connect the serial cable between the host and the terminal and verify normal operation of the host, then turn off the host,
  • place schottky diode D4 next to J3 on the host, this provides 3.3V to J3 when the host is powered,
  • install the header at J3 on the host,
  • add a 2K resistor between pins 1 and 2 of J3 on the host, this compensates for a weak pullup,
  • install the header at J2 on the target,
  • connect using the IDC cable observing connector polarity,
  • add power cord to host only.

Alternate Setup

  • in place of schottky diode D4, short the D4 component position next to J3 on the host, this provides 3.3V to J3 when the host is powered, but without protecting the host from power flowing from the target, be sure not to power the target,
  • in place of the headers and the IDC cable, use six 15cm lengths of wire, and link each pin of J3 on the host to J2 on the target in turn,

Transfer

  • turn on the host, while on the terminal use ESC to interrupt the host startup and obtain the Ok prompt,
ok
  • clone the SPI FLASH:
ok clone
Getting a copy of this machine's FLASH
SPI FLASH type is 13 - Spansion, Winbond, or ST
Writing
d0000
Writing
f0000
Verifying
d0000
Verifying
f0000
ok 
  • turn off the host.
ok power-off

Testing

  • disconnect the cable between the target and the host,
  • attach serial cable to target,
  • attach power cable to target,
  • test the target by using ESC to obtain the Ok prompt.

Reasssembly

  • remove the header or ensure internal plastic is cut to permit it to remain.

Training Video

xo-1.5-debrick.mp4 (69 MB)

Uses an alternate setup, with machine pin IC socket pins as connection points instead of IDC headers.

Errors in the video:

  • the diode at D4 is normally not populated, it is the position that is shorted, not the diode,
  • a 2k2 resistor was used in place of 2k0,
  • clone is pressed, ignore,
  • an irritating lighting strobe,
  • went on for too long when stop button was not pressed early enough.
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