I recently managed to reactivate my dear old Epson HX-20, a retro computer released in 1983 which I used at the end of the 1980’s and early 1990’s to learn programming. Since I even could read in some BASIC programs that were still stored on the micro cassette, I wondered if I could rescue the code directly, without using OCR on printouts or even typing it off by hand. I was aware that I was very lucky that this machine still worked after all those years—the soldering seemed to have been much more rigid back then, it might cause more issues to attempt to run old PCs which are a decade younger! To be on the safe side, I invested into a new NiCd battery pack and replaced the original one.

My research first led me to the machine’s RS-232 output, internally called “COM0”. Someone had used that some years ago to directly connect an HX-20 to a PC’s serial port, using a special cable and some adapters. Sadly, it seems that this is no longer an option, since these cables disappear, and serial-to-USB adapters only seem to work with a certain chip in this case.

Then I stumbled upon the GPL software HXTape, and I was totally baffled: What, the Epson HX-20 had an external cassette interface as well? I knew that concept from our even older machine, the Texas Instruments TI-99/4A. It connected to a special music cassette recorder and encoded data into simple “magnetic bits” onto the tape:

It was quite funny to listen to the noisy sounds when playing the MCs on an ordinary player.

This bidirectional data transfer works over ordinary mono audio cables, one for each direction. And now, it turns out the HX-20 had such an interface as well, and we never used it. But the point is, one could exploit it to decode the audio signals into the original bits and bytes by connecting the HX-20’s “MIC” port to the microphone input of a PC using a simple mono audio cable with standard 3.5 mm jacks! (How tremendous the analog world was! Keep a music cassette lying around in the basement for decades and then just play it. Try this with your ¡Phone!) And that audio decoding is exactly what HXTape is doing.

Eight years ago, I wrote in the history of my computer usage,

In 1988, when I entered grammar school, [...] I did a bit more serious BASIC programming on an Epson HX-20, which I still own today, but isn’t working anymore. [...] My cousin René taught me some BASIC things like how to use the random number generator.

Well, it turns out that this machine is still alive, as you can see in this video:

You can even watch me loading my cousin’s learning program from the micro cassette—that very lines he’d written for me on Dec 29th, 1988. Though, its output was designed for a separate and larger screen that I don’t own anymore.

I’m pretty sure that this machine had slept from ~1995 until I woke it up now. I hope I can also have a look at my other programs on that micro cassette.

Being so content with Wuala’s features I gulped when I read that they shut their service down. At least they partnered with Tresorit, another Swiss zero-knowledge cloud storage provider, to provide a dedicated transition path. Tresorit had failed for me in my research last year, because they didn’t provide a Linux client—meanwhile, they do, but it’s still a beta. In addition, there’s no easy way to test their service other than during a 14-day trial. [Update 25 Aug: The trial period is now 30 days.]

Rather than looking at what they had in common, I checked Tresorit against my usual requirements, and sadly, it misses a few points:

• There’s no on-demand-only download of files like in Wuala. You either sync 100% of a GB-heavy “Tresor”, or not at all. In Wuala, you could browse through the directory tree without allocating much disk space. [Update 25 Aug: Their desktop client is also a cloud file browser, where you can explicitly download files from unsynced Tresors.]
• The client doesn’t provide an unencrypted view of an encrypted data container on the disk while it runs. If the client shuts down, the files remain plainly unencrypted in the file system like with Dropbox. [Update 25 Aug: Files remain unencrypted only if you actually sync a Tresor.]
• There’s only a Premium plan with 100 GB for one user, or a Business plan with 1 TB for at least two users. If you only need 200 or 300 GB, you’re out of luck, as it seems. [Update 25 Aug: For Wuala switchers, their Business plan is now also available for a single user, what means 1 TB for just double the price.]

Luckily, they have planned to implement the first two, but that could take a while.

And, other than Wuala’s and Tresorit’s recommendation to export Wuala’s data once and import it as a single Tresor into Tresorit, I found out it’s much better to reorganize Wuala’s subfolders into dedicated Tresors. This makes sense, because you can configure which Tresors to sync on each machine. This way, you could e.g. create a dedicated Tresor for each employer and sync only that, so you don’t accidentally put private or third-party data onto your employer’s machines. Should you need access to one of those unsynced Tresors, though, you either do have to sync it (100%), use their web client (but file download failed in my first test), or use one of your mobile clients. [Update 25 Aug: Their desktop client is also a cloud file browser, where you can explicitly download files from unsynced Tresors.]

But, so far their service looks promising. Their clients are much more modern; e.g. Wuala’s Java desktop app or Android app have been an inferior UX. I neither know Wuala’s nor Tresorit’s user numbers, but that kind-of “merger” might generate a user base that helps Tresorit survive for a while.

And never forget: Any item in the cloud should only be a copy of an item on one of your disks.

I’m using Wuala’s cloud storage for some years now, and I tried to challenge the status quo to see if there are better alternatives available in the meantime. The main requirement for me is a zero-knowledge provider, a provider that does not know my password and cannot decrypt my data (without brute force). I found these candidates:

Wuala, Tresorit, SpiderOak, MEGA, SeaFile

(Note that SeaFile is a self-hosted open-source solution.) The next requirement is location: Servers should not be located in the USA, and there should be an Android client that supports upload ...

Wuala, Tresorit, SpiderOak^{Double-Plonk!}, MEGA, SeaFile

... and there should be an official Linux client ...

Wuala, Tresorit^Plonk!, MEGA, SeaFile

... and the service shouldn’t require exotic TCP ports such that clients work behind a corporate firewall ...

Wuala, MEGA, SeaFile^Plonk!

... and the service should support file revisions, download on demand only, and files should stay encrypted on client exit ...

Wuala, MEGA^{Triple-Plonk!}

Way to go, Wuala!

... GSM version (Maguro) with Android 4.3 from GNU/Linux

I found so many incomplete tutorials written in bad English that I decided to write one myself and keep it simple. You must have your phone’s bootloader unlocked; doing so will wipe your device!

1. Watch this tutorial video.
2. Download the fastboot and adb binaries, e.g. from the Universal Nexus Linux Toolkit. Extract the archive on your machine. Find the binaries.
   The problem with this toolkit is that the bundled zips are rather old and didn’t work for me, so:
3. Download the ClockworkMod recovery image from here.
4. Download the SuperSU zip file from here.
5. Connect your phone to your PC via USB.
6. Boot your phone into bootloader mode: Power it off, push both the volume rocker up+down and then press the power button, i.e., press all three at once for about two seconds.
7. ./fastboot oem unlock if you haven’t ever done it. This will wipe your device, reset it to factory settings and delete all your data. Yes, really.
8. ./fastboot flash recovery /path/to/recovery-clockwork-6.0.4.7-maguro.img
9. Now load the recovery: Volume button down twice to choose Recovery mode, power button to select.
10. Navigate using the volume rocker: “install update from zip”, press power button to select, choose “install zip from sideload”, press power button.
11. ./adb sideload /path/to/UPDATE-SuperSU-v1.93.zip
12. Navigate back and reboot normally. Your installed apps should now show SuperSU installed.

Have fun!

Some quotes of myself from four years ago:

“Cheap” should mean here that you don’t need to spend money on extra hardware like a remote timer or on extra software like Windoze [...]

My hope is that I can use gphoto2 with an Android smartphone.

Somehow this is still a Linux-post, as Android simply is the most popular Linux distribution to date. Btw, PC and smartphone don’t count as dedicated extra hardware. But you might need to purchase an app and a USB adapter:

Meanwhile I use the awesome DSLR Controller on my Android smartphone in USB host-mode to create time-lapse picture sequences on my aging Canon EOS 40D—a thing that wouldn’t work with a diePhone, I guess. This app can do a lot more, of course. Up to now, you have to rely on USB. However, as Wi-Fi enabled DSLRs are appearing, there is some hope to get rid of that cable and adapter one day; Canon’s own EOS Remote app doesn’t support time-lapse shooting yet. [Update: To equip your camera with Wi-Fi, you could hack an Android TV stick!]

The most elegant solution would of course be located within the camera itself. Canon is still sleeping in this regard, but at least there’s the third-party Magic Lantern firmware add-on for some newer models, also sporting an intervalometer. My 40D is not (yet, but I guess won’t ever be) supported.

You should still set the camera to a resolution at or slightly above the HD 1080p resolution, which in my case is 1936×1288. You should fix the aperture and ISO values, and probably also the exposure time. [Update: In addition, fix the white balance. Also, don’t forget to cover the viewfinder with the eyepiece cover on your strap, as otherwise you might get different exposures that result in flickering!]

After getting the images to your Linux machine, you need to crop the pictures from 3:2 to 16:9 (in my case 1936×1089) or crop a 1920×1080 patch directly. You can do this with a simple script using ImageMagick:

(GNU Parallel didn’t work for me.) You can then issue

to render an HD video into a format that’s also recognized by your smartphone.

Finally, you could use OpenShot to edit your videos and add background music. (You could of course compose that music yourself using FOSS as well...)

... or, actually, to Perl’s Finance::Quote, under Ubuntu 11.10:

1. Clone one of the source modules in /usr/share/perl5/Finance/Quote (came with libfinance-quote-perl), say, Morningstar.pm, and place it under a new name into /usr/local/lib/perl/5.12.4/Finance/Quote, say, as Morningstar/AT.pm. (That’s what I did, I’ll probably make that module available.)
2. Modify this module into a uniquely new entity, providing appropriate IDs, like morningstar_at.
3. `perl -e ‘use Finance::Quote::Morningstar::AT’` should not display anything—especially no error.
4. Copy /usr/share/perl5/Finance/Quote.pm to /usr/local/lib/perl/5.12.4/Finance and add Morningstar::AT to @modules.
5. Execute `gnc-fq-dump | grep --color=auto morningstar`, you should see both morningstar and morningstar_at.

Your new quote source should now be available to GnuCash:

6. Go to Tools → Security Editor → Add (or Edit) and enter the appropriate “Symbol/abbreviation” and “ISIN, CUSIP or other code”—note that the symbol is not the ISIN in the case of Morningstar.at, it’s the ID in the URL! Check Get Online Quotes, switch to Unknown and select morningstar_at.
7. Go to Tools → Price Editor and click Get Quotes. After a few seconds you should see new entries with the current prices.

Since I plan to back up my worthy RAW pictures into the cloud (Why?), I collected some reference values of various cloud storage providers with the following important conditions in mind:

1. Support for GNU/Linux
2. Support for Android
3. Available for Europeans

The following graph lists the various providers I found and plots their available volume packages against their prices:

All prices are per year, with a fixed exchange ratio of 1 EUR = ¹⁰∕₇ USD. Lower is better. Dashed lines indicate a violation of the proposed conditions—see below.

In the following I provide a short summary for each provider, and a conclusion of my personal considerations.