Stepper Motor Controller a la Arduino

This is a relatively easy recipe, for beginners. The idea behind the project was that there was a need for fine stage control in the laboratory and a Thorlabs motorized actuator (like the old ZST25 or the newer ZST225B) + controller can be quite expensive. So I made my own Harder, Better, Faster, Stronger version.

Continue reading “Stepper Motor Controller a la Arduino”

FreeBSD 10 installed with tftp on a Amilo L7320

The Background Story: TL;DR

I had a little spare time this weekend, and wanted to put a new OS on my Fujitsu Siemens Amilo L7320. The laptop is now ~8 years old, and my opensource deep-dive started with it. I installed my first Ubuntu 7.10 on this machine to replace the preinstalled Windows XP. And no dual booting, no turning back! (sadly this changed…)*

It was a deep dive, because X11 was not working and I had to hack my own xorg.conf. I hate the Via Unichrome GPU, but around Ubuntu 10.04 the openchrome driver was doing it’s job out of the box. The CD/DVD drive died after 1,5 years (before 9.10, so I had to make my on TFTP/PXE install server. You might ask why didn’t I use a USB Stick, and boot from a “USB Storage Disk” as the bios suggests. Well, the machine won’t boot from any USB Installer, because “Invalid partition table”. So no iso dd/imgwriter. It can boot from grub2 or lilo, so it needs a mbr? I don’t care. TFTP/PXE is good for me. And there were other problems, like the clock and the whole system hanged if there was no user input or cpu load (this was on kernel 2.6.35 and some more kernels above). But with Xubuntu 12.04.5 the machine was working OK. But it was time to make the change and try a new OS…. FreeBSD. Thanks to Allan & Kris. Continue reading “FreeBSD 10 installed with tftp on a Amilo L7320”

Asus Fonepad 7 (FE170CG) firmware update misery

So you bought a new phone+tablet from ASUS and accidentaly failed an update? Well you are at the right place, because I was in the same shoe. Note: This is for the WW version. If your’s is on a different SKU then you must stay on that path.

Recovery from a failed update:


  • You wanted to update from Jelly Bean (4.3) to KitKat (4.4) using an update from the asus website.
  • During the update an Error message showed up.
  • When you want to start your device it only shows an usb logo for a second.

Origin of the problem:

  • You applied the latest kitkat update on a jellybean firmware.


  1. Download the from ASUS site.
  2. Unzip the archive.
  3. Rename to
  4. Copy the renamed file to an SD card, and insert it to the device.
  5. Start the Phonetab in Droidboot by pressing and HOLDING Volume up and Power button until the menu appears.
  6. Select Recovery.

How to do a proper update to KitKat?

  1. Start from the latest Jelly Bean.
  2. Apply the first KitKat update:
    1. Rename to
    2. Copy it to the SD card.
    3. Reboot into Droidboot.
    4. Select SD Upload.
    5. Optional: Do a Wipe.
  3. Apply the next KitKat update:
  4. And so on… (or you can now safely jump to the latest one:

You can be paranoid (apply all updates in order) or semi-paranoid (apply only firs KitKat and move to the latest). But don’t skip immediately from Jelly Bean to KitKat.

What is IFWI?

Intel FirmWare Interface – a blob to load kernel. Like a PC BIOS.

About Lollipop updates

Please don’t upgrade to Lollipop yet. You might get it via OTA or via the Asus download page. But ignore it.

You will loose DualApp, the memory usage and the internal storage usage will increase.

I recommend waiting for a more updated version of lollipop (not WW_12.8.1.38 , and not WW_12.8.1.33), because you cannot downgrade!