Sunday, May 21, 2017

Reading picture books for children

During the last year, I have been invited several times to participate in a group of volunteers that read picture books for children in different languages. This kind of groups, called dantai in Japanese (団体), are very common in Japan. If you want to participate in one you just need to ask at your closest cultural/community centre (search for 文化センター,市民センター,コミュニティセンター, or 区民センター).


One of the books that we read very often is "The very hungry caterpillar". The title is translated as "La oruga muy hambrienta" in Spanish and "Harapeko aomushi" in Japanese. We also read other books including my own.


A month ago I went to see an exhibition of the author of "The very hungry caterpillar", Eric Carle, at the Setagaya art museum. Eric Carle's paintings were really interesting from the technical side as well. Many of them were a collage of pieces of semi-transparent textured paper painted with acrylic colours.

Saturday, May 20, 2017

OSC 2017 Spring

The Japanese Open Source Conference, usually known by its initials OSC in Japan, is a great event for open source enthusiasts. It is celebrated in different japanese cities and regions throughout the year such as Tokyo, Hamanako, Osaka, Hiroshima, Fukuoka, Kyoto, Nagoya, and many more. Here is their official OSC Twitter account.


Although I have attended the conference many times I had only reported once in 2013. This time I attended Tokyo OSC 2017 Spring which was held at Meisei University, a private University that has great rooms with multiple screens.



During the conference I made a short introduction to Fuego, an open source test framework that I'm contributing to recently. You can find the slides here. This wasn't my first presentation in OSC but it was the first one I did as part of my job. You can also find the videos and slides of other presentations given during the conference here. I was very interested in the Lagopus project, which supports DPDK (a cool framework for zero-copy network applications); the Vuls vulnerability scanner; and also Volumio, a Hi-Fi digital music Linux distro.


Although I normally use the Tama Dōbutsuen Station which is right in front of a zoo (Dōbutsuen means zoo), about 15 min walk to the OSC building, most people prefer to use the Chuo Daigaku-Meisei Daigaku Station on the Tama Monorail. Here is a picture of it on my way back to the station.

Conclusions: it's always fun to attend the OSC and learn about new trends, software and make new friends. Also I think it is especially fun if you make your own presentation.

Wednesday, May 17, 2017

Assembling a dsPIC-based DIY oscilloscope

In August 2015, I attended a Tokyo Hackerspace event called building a DIY oscilloscope. However, it wasn't until December 2016 that I finally assembled and tested it!.


During the event, we received a kit from Carl Blaksley that was based on an original design by Ajoy Raman. The hardware is quite simple and consists of 3 main components: the analogue interface, the processor and the USB interface. The analogue interface includes a few RC filters and 2 programmable gain amplifiers (SPI protocol) MCP6S22 (one for each channel). The amplified signal is then sampled by the processor, a dsPIC30F2020 which contains a 10-bit 2 Msps ADC (shared among the channels enabled). Finally, the USB interface is handled by the famous USB-serial FT232RL chip. Carl was nice and sent me the Kicad design files of the board. The assembly went quite smoothly but as always I had to debug a hardware problem that ended up being caused by my USB (a cross USB cable was needed).


The software was written in python and worked fine on Ubuntu 16.04 (there is also a visual basic version for Windows). To test it, I installed this amazing Android function generator application and connected it to the oscilloscope through a 100yen (sold at Seria) headphones stereo amplifier.

Saturday, April 22, 2017

Deciphering Akihabara signs

When I first came to Akihabara I couldn't help but feeling frustrated by the fact that I wasn't able to understand most of the signs on its buildings. 10 years later I don't have such problem anymore. In this post, I want to give you sort of a glimpse of what kind of stuff is written out there.


Let's start with the easy ones. If you learn katakana, which consists of only 48 characters, you'll be able to read quite a few words and luckily guess their meaning. (1) has カラオケ written on it which reads Karaoke, so that whole building is full of karaoke rooms. There is another sign in that building that starts with 本 (hon = book) and continues with Book Off. Book Off is a famous franchise where you can buy (and read) second-hand books and manga. (2) has ラジオセンター which reads as rajio sentaa and means radio centre (could you guess it?). Radio centre is almost a historical place already, full of electronic veterans in small stands selling electronics, amateur radio equipment and lots of retro stuff. (3) GEO is the name of a well-known DVD, Game and Manga rental franchise. But it seems it's started a mobile offering. On this sign you can see the words 格安スマホ (kakuyasu sumaho = supercheap smartphones) written. 格安 is often used on signs so it's easy to remember. (4) This one has English on it so you should know what it is about. インターネットまんが喫茶 (Internet Manga Kissa = Internet & Comics cafe) is a place where you can chill and rest your feet. Usually you get your own little compartment where you can seat, use a computer with Internet, read comics (if you are able to) and have some soft drinks. The value for the price is really good and it's something you can only experience here. In smaller characters you can read 完全分煙 (Kanzen Bun'en = smoking and non-smoking areas are completely separated), シャワー完備 (shawaa Kanbi = Fully-equipped Showers), スマホ充電OK (sumaho juuden OK = it's OK to charge your smartphone), 24時間営業 (24 jikan eigyou = 24 hours business), コムコム秋葉原点 (komukomu akihabara ten = komukomu akihabara shop, where komu means that it gets full of people), 当ビル5F受付 (toubiru 5F uketsuke = reception on the 5th floor of this building). Below the sign we have a 麻雀 mahjong shop saying ウエルカム which you should understand if you learned katakana (welcome). And right below that, on the 2nd and 3rd floor (in Japan the count starts at 1) we have a maid cafe, another place you should try at least once. On the first floor we see the 24時間 sign again, and 富士そば (Fuji soba) where you can eat soba. (5) We see まんが喫茶 again and then 免税商店 (menzei shouten = tax-free shop) which are all around in Akihabara. 歓迎光臨 is Chinese but the first two characters have also meaning in Japanese (歓迎 Kangei = welcome), so basically they are targeting potential Chinese/Taiwanese buyers. (6) Akihabara is the land of anime and games. Just by taking a look around you can catch up with the latest trends or learn of new anime series to come. 明日のステージへ! (ashita no suteeji e) means something like "towards tomorrow's stage). TVアニメ好評放送中 (TV anime kouhyou housouchuu = TV anime with good critics currently on show) is something you find all the time when you walk into an anime or manga shop. Below that sign we can see 日本武道館, this is Nippon budoukan a place where many famous music bands have played. Not surprising we can see there's going to be a live performance (note that the anime, BanG Dream, is about music) there on the 21st of August, 2017. チケット最速先行 (chiketto saisoku senkou) means that tickets are sold on a first-come-first-served basis. If you read this now, you can go to the BanG Dream official site and see the same advertisements about the "4th Live". In this kind of concerts you can see the people that are behind those anime songs and voices you like so much. (7) We see again another sign about BanG Dream, it must be something big. But let's decipher the sign in black&red. 鉄道模型 (tetsudou mokei = train models) is a shop where they sell stuff for making your own train models. This area in particular has many other shops for modeling trains, tanks, planes, gundam figures and stuff like that.



I had 2 more pictures to decipher but I guess this post took already too long. I will let you "relax" watching a few excerpts from a BanG Dream's live!.

Conclusions: the main takeaway from this post is that if you come to Japan for the first time and you want to understand something from what's written on Japanese signs, then you better learn katakana. That will help you understand words such as rajio (radio), sentaa (centre), sumaho (smartpho[ne]), shawaa (shower), uerukamu (welcome), suteeji (stage), intaanetto (internet), biru (buil[ding]), or chiketto (ticket).