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Resources
- Photography
- Projects
- Publications (see also: ESS, ORCID, DBLP, Google Scholar)
- Recipes
- Repositories (partial mirrors: GitHub, Chaosdorf)
- Weblog (Fediverse Microblog: @derf@social.skyshaper.org)
- Whatever
Contact
You can reach me by E-Mail (derf@finalrewind.org) and on IRC (derf0 @ OFTC, hackint). My PGP key for E-Mail encryption is 64FE6EC0 55560F9E F13A3044 19E6E524 EBB177BA. I occasionally post stuff on the Fediverse (@derf@social.skyshaper.org).
The remainder of this page duplicates a curated sub-set of projects and the latest blog entries.
Projects
> hafas 'Eichlinghofen H-Bahn, Dortmund' 'Dortmund Hbf' 00:15 Schw-B HB5 (0:03) S 1 Schw-B HB5 → Universität S-Bahnhof, Dortmund 21:51 ab Eichlinghofen H-Bahn, Dortmund 21:55 an Universität S-Bahnhof, Dortmund Walk 37m (approx. 3 minutes) S 1 → Dortmund Hbf 21:58 ab Dortmund Universität: 2 22:06 an Dortmund Hbf: 4
> efa Essen Martinstr Düsseldorf Hbf 14:34 ab Essen Martinstr.: Bstg. 1 Straßenbahn 108 Essen Altenessen Bf Schleife 14:38 an Essen Hauptbahnhof: Bstg. 1 14:47 ab Essen Hauptbahnhof: 2 R-Bahn RE11 (RRX) Düsseldorf Hbf 15:24 an Düsseldorf Hbf: 10
> hafas-m 'Hamburg Dammtor' 13:49 ( +1) RE 7 Flensburg 3 13:49 ( +1) RE 7 Kiel Hbf 3 13:49 S 5 Buxtehude 2 13:50 ( +4) Bus 5 Nedderfeld, Hamburg 13:50 U 1 Ohlstedt, Hamburg
> efa-m -s VVO Dresden Hbf 13:40 ( -2) 5 66 Lockwitz 13:41 3 3 . Wilder Mann 13:44 4 3 . Coschütz 13:44 6 66 Freital-Deuben 13:46 ( +4) 6 360 Kurort Altenberg Bahnhof 13:46 5 360 Dresden Ammonstraße / Budapester Straße 13:48 ( +1) 1 7 * Weixdorf 13:51 1 10 . Tolkewitz 13:52 Gl.10 RE3 Hof Hbf
News
Travel::Routing::DE::HAFAS v0.09
Travel-Routing-DE-HAFAS-0.09.tar.gz (signature)
- Improve handling of backend messages and errors
Travel::Status::DE::VRR v3.03
Travel-Status-DE-VRR-3.03.tar.gz (signature)
- efa-m: handle undefined platforms
Trip->polyline
: passfallback => 1
to return beeline between stops if the backend did not provide a polyline.
Travel::Status::DE::VRR v3.02
Travel-Status-DE-VRR-3.02.tar.gz (signature)
- Stop: Add
ar_delay
,dep_delay
,delay
,stop_id
accessos - EFA: Fix
place_candidates
- EFA: Add stop and stops functions
- EFA: Add static g
et_services
method - efa-m: Add -
j
/ --with-jid
option - efa-m -Oa, -Ob, -Of: Show delays
- EFA, efa-m: Add stopfinder ("?foo") and stop search ("lat:lon") modes
- Add ...::Trip and ...::Info modules
- Info, Stop, Trip: Note that the API of these modules is not yet final and may change between minor versions
Travel::Status::DE::DeutscheBahn v6.11
Travel-Status-DE-DeutscheBahn-6.11.tar.gz (signature)
- HAFAS: Add mobiliteit service definition
Travel::Status::DE::VRR v3.01
Travel-Status-DE-VRR-3.01.tar.gz (signature)
- Fix
Departure->route_interesting
- efa-m: Add
--json
option
Travel::Status::DE::VRR v3.00
Travel-Status-DE-VRR-3.00.tar.gz (signature)
- Drop
XML::LibXML
dependency - New dependencies:
DateTime::Format::Strptime
,JSON
- Switch API language from XML to JSON
- Rename
Travel::Status::DE::EFA::Result
toTravel::Status::DE::EFA::Departure
- EFA: Add static
get_service_ids
function - EFA: Add bwegt backend service
- EFA: Remove
identified_data
accessor (not supported by JSON backends) - EFA: Remove static
get_efa_urls
function; useget_service_ids
instead EFA->new
,EFA->new_p
: Add optionalcache
key- Result/Departure: Add
hints
accessor - Result/Departure: Remove
info
accessor; usehints
instead - Stop: Add
place
,full_name
andoccupancy
accessors - Line: Add
number
accessor - Stop: Remove
name_suf
accessor; usename
instead - efa-m: -Oa, -Ob, -Of: show per-stop occupancy, if available
Travel::Status::DE::DeutscheBahn v6.10
Travel-Status-DE-DeutscheBahn-6.10.tar.gz (signature)
- HAFAS: Hardcode request seconds to 00 to improve caching
- hafas-m: Cache backend replies by default (if Cache::File is available)
PowerCore 5000 Teardown and Repair
I usually carry a PowerCore 5000 powerbank with an attached USB-A to USB-C cable in my purse. In hindsight, always having the cable attached to it (rather than just when using it) is not the best idea, as it exercises quite some leverage forces on the USB port. So, to little surprise, at some point the output port stopped working unless the cable connected to it was pressed into the right direction.
Luckily, the powerbank is quite easy to open up, repair, and re-assemble.
Caution: This powerbank contains a 18.5 Wh LiIon cell. In normal operation, the (dis)charge PCB is in charge of battery management tasks like short circuit protection. Disassembly exposes the raw 26650 LiIon cell, which likely does not contain a built-in protection circuit. Puncturing, shorting, heating, or otherwise mishandling it can lead to fire and/or explosion. Don't disassemble a powerbank unless you know what you are doing. Don't work with soldering irons close to LiIon cells unless you really know what you are doing.
Teardown
The connector side of the power bank features a glued-on plastic cover on top of a screwed-on plastic cover.
The glued-on cover can be pried open with moderate effort by placing a suitable object between the two plastic covers, revealing the screwed-on second plastic cover.
With the powerbank placed on a table (not held in your hands), you can now take a PH00 screwdriver to release the three screws that hold it in place. Once that is done, simply lift the case up, revealing the actual circuitry (LiIon cell and PCB). If you were holding the powerbank in your hands while removing the screws, the circuitry likely fell out instead.
The innards are quite simple: A single 26650 LiIon cell; a single PCB; and a two-part plastic assembly featuring a button and LED diffusors.
Repair
In my case, the culprit was a loose solder connection between the USB-A output port and the PCB. Nudging the capacitor out of the way and carefully applying some additional solder to its GND and VCC pins solved the issue. Just be wary of the fact that you're operating a soldering iron next to a LiIon cell that does not like triple-digit temperatures…
Re-Assembly
- Slide the button assembly and diffusor back into the case until it locks into place.
- Slide the LiIon cell and PCB assembly back into the case.
- Place the powerbank on its bottom (i.e., so that the USB ports face up).
- Place the plastic cover on top of the PCB assembly and tighten its three screws.
- Put the glued-on top cover back on. It comes with alignment pins; in my case I did not have to apply new glue.
Travel::Status::DE::DeutscheBahn v6.09
Travel-Status-DE-DeutscheBahn-6.09.tar.gz (signature)
- Improve handling of services which do not provide intermediate stops
- HAFAS: Add Resrobot service definition
- HAFAS:
get_service
et al.: return coverage data provided by transport-apis, if available
Travel::Status::DE::DeutscheBahn v6.08
Travel-Status-DE-DeutscheBahn-6.08.tar.gz (signature)
- HAFAS: Add DSB (Rejseplanen), TPG and ZVV service definitions
- HAFAS: Update endpoint URL for BLS service
Travel::Status::DE::DBWagenreihung v0.18
Travel-Status-DE-DBWagenreihung-0.18.tar.gz (signature)
- Group: IC2 trains have designations as well
- Group: Add static
name_to_designation
accessor
Travel::Status::DE::DeutscheBahn v6.07
Travel-Status-DE-DeutscheBahn-6.07.tar.gz (signature)
- HAFAS: Fix enum error in ÖBB service
- HAFAS: Add RSAG service definition
Travel::Status::DE::DeutscheBahn v6.05
Travel-Status-DE-DeutscheBahn-6.05.tar.gz (signature)
- HAFAS: Add KVB service definition
- Use mode of transport definitions provided by https://github.com/public-transport/transport-apis
Travel::Status::DE::DeutscheBahn v6.06
Travel-Status-DE-DeutscheBahn-6.06.tar.gz (signature)
- HAFAS: Remove undocumented Math::Polygon dependency that was accidentally added in 6.05
- HAFAS: Add STV, RMV, VMT, VRN service definitions
Travel::Status::DE::DBWagenreihung v0.17
Travel-Status-DE-DBWagenreihung-0.17.tar.gz (signature)
- Group: Fix
->name
accessor (thanks to Caß Dingenskirchen) - Group: Add
->designation
accessor (data courtesy of bahn.expert)