Nandblaster for XO-1.5


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Quick Start


How to install to multiple XO-1.5 using NANDblaster:

The build is installed to the internal microSD device. You will need a USB drive of at least 1Gb capacity, but only for the duration of the installation.

  • Prepare the USB drive:
    • download the os*.zd file for the build you wish to install,
    • copy the file to the USB drive,
    • rename the file to fs.zd,
    • check that the USB drive contains the file fs.zd,
  • Prepare the sender laptop:
    • choose a laptop, it must be an XO-1.5, it need not have anything installed on it, and if there is a build installed on it won't be changed by the process,
    • check that the laptop has firmware q3a50 or later, upgrade the firmware if needed,
    • unlock the laptop if it is locked,
  • Start the sender laptop:
    • insert the USB drive in the laptop,
    • power up to the Ok prompt,
    • type nb-update and press enter,
    • wait for it to get going, it is ready when you see "pass 1" and a slowly increasing block count ... it usually takes about 15 seconds,
    • leave the USB drive in the laptop,
  • Start the receiver laptops, one by one or at will if you have many people helping:
    • hold down the four game keys while turning on each laptop, (you may here an interrupted startup sound, this is normal),
    • watch the display until the coloured boxes begin to appear,
  • If a receiver laptop does not properly start:
    • ensure they have firmware q3a45 or later, upgrade the firmware if needed,
    • try once more, wireless contention may have prevented association,
    • move it closer to the sender, try once more, radiofrequency noise may have prevented association,
  • Wait for all receiver laptops to finish. To assess the state of a laptop:
    • if the left-hand wireless LED is on, and a black outline is moving over the screen, then the laptop is listening for data,
    • if the blocks are mostly pink, noise is hindering reception,
    • if the blocks are mostly yellow, then noise. distance or a broken antenna is preventing reception; the laptop should be moved closer to the sender,
    • if the blocks are filling in green, and the storage LED is flickering, then the laptop is finished listening and is writing data to internal storage; the laptop may be moved away from the sender,
  • Stop the sender laptop:
    • press File:Esc.png Escape key on the sender laptop,
    • power it off,
    • remove the USB drive.

Starting the Sender

NANDblasting an Unsigned Filesystem Image File

To send an unsigned filesystem image, put the filesystem image file (*.zd) on a USB drive as "/fs.zd". Insert the USB drive into the sending XO and type:

 ok nb-update

NANDblasting a Signed Filesystem Image File

To send a signed filesystem image, put the filesystem image file (*.zd) on a USB drive as "/fs.zd". Put the corresponding signature bundle (the .zip that contains a control file and a signature file) on the USB drive as "/". Insert the USB drive into the sending XO and type:

 ok nb-secure

Cloning the sender's Filesystem

Cloning the sender's filesystem (nb-clone) is not available on XO-1.5. See Imaging_for_XO-1.5 for an alternative.


You can stop the sender by typing the ESC key or by powering off. If you type any other key, the sender will pause and ask you if you want to stop. If you then type 'y', it will stop; other keys will resume the sending.

"No quiet channels" - Forcing the Channel

The sender chooses a wireless channel automatically by scanning to find the least-busy channel. If they are all busy, i.e. they all have received signal strength values exceeding some threshold, the sender tell you which one has the least signal strength and ask for confirmation before proceeding on that channel.

You can force it to use a specific channel by appending either "1", "6", or "11" to one of the commands above, for example:

 ok nb-update6


 ok nb-secure11

If you force the channel, the sender won't check if the channel is busy, it will just start sending.

Changing the Redundancy

You can change the redundancy percentage before you execute one of the send commands. For example, to set the sender redundancy to 12% (the default is 20%), type:

 ok d# 12 to redundancy

The redundancy controls the number of extra error correction packets that the sender sends for each erase block worth of source data.

Design Notes


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