Electrogeek.tokyo

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2024-09-24 - Ridiculous II
Continuing in my "do what I say not what I do" about staying focused, I wrote another app over the weekend:

Dictee-Tor: a web app to allow kids to do dictation by themselves without parents reading them words. It grew on a feature request from my boy, and continuity of the other Seyes Wordlist project. Put the words in a DB, reusing the Voice RSS text-to-speech API (thanks to them for the free tier), little logic and voila.

Available as an app standalone or Docker image (built it yourself for now).
screenshot

2024-09-05 - Ridiculous
I just talked about staying focused earlier this week. I'm not. I must be bored at work because 2 evenings I made 2 nice and functional projects!

Seyes Wordlist that generates a Seyes type paper with a wordlist you pass to it, because my kid is learning to write.

MorningMetroMonitor because it took me 3 hours (!) to drop them to school last Thursday, this thing parses Yahoo Japan Transit page, get my usual path and every morning pings me on Naver Line to tell me if it looks like the trains run smoothly or not. At least I'll know and save some time.

Both projects worked fine from the beginning which is scarry (too good to be true!). Anyway time for bed, after 2 evenings of well done geeking.

2024-09-03 - Try to stay focused, damm*t

That picture, is the story of my interior self creative life. I have new ideas so often, most often worthless, but it's an itch I have to scratch.
Latest in date, this morning I became permanent resident of Japan (yay me!) and I need to renew it in 7 years precisely or univers will collapse. I need to remind myself of this. How? Will I still use Google calendar at that time? Is there no way to set memos for a far future?
Why not make it myself?!

Use Line chat bot

NLP commands like "remember event 'renew my visa' in 6.5 years" or "...at 2031/01/01"

Chat bot in python Flask (what else?) in a container (newest learnt tech) and a a small DB

Send reminder via mail, Line, etc.

Companion web app, also Flaskontainer'd

I might do it. Or not. We'll see :D

2024-09-02 - Bananas
In the big family of Raspi clones, I have an Orange Pi 2 and last year I acquired some small Raspi ZeroW clones, Banana Pi M2 Zero. And of course things didn't go as planned once I needed them so let's share my experience here.

2024-08-25 - Networking
Like many geeks I have many servers, physical or virtual, running in different places of the world. I recently started doing SSH Tunnelled HTTP local port forwarding, so I can access locally from a resource on the network of the SSH server (using it as a proxy). Useful because my tiny SSH server is a gateway to the internal NW that under no normal circumstance should have "unchecked" access to the outside world.
That allows me to manage my wifi router remotely. Not that it's useful in any measure, but it pleases me that I can.

ssh -l [REMOTE ID] -i ~/.ssh/id_rsa -p 22 -L 8888:192.168.2.1:80  [REMOTE SERVER IP]

Connects you with the [REMOTE ID] login and the id_rsa key (or remove that if you use a password) to server [REMOTE SERVER IP] on port 22

Plugs your local port 8888 to the 192.168.2.1:80 via the remote server as a proxy

Now open http://127.0.0.1:8888 and play with your remote network router.

2024-08-21 - Japan summer is too hot
Wow Japan summer is hot, and I didn't do much electronics. I mainly dabbed in Python and website devs, and learned a bit of Docker for my Poke-Trainer app.

My old house came with strange fans attached to the wall to address the rampant Japan humidity and meant to be permanent low power air circulators ... but none of them worked from the day we moved in. Granted they are old enough to vote but one can hope, no? Anyway couple weeks ago I removed one from the wall, cleaned the dead Huntsman spiders and the wasp nest I found inside, but still it didn't work.
Tried all I could and thought it was the AC motor that was dead (spinning well manually but the axis is a rust-covered lollipop). So I went medieval on it, and verdict: the AC engine is fine! What broke? The board that controls the High-Low speed (via a couple of high power resistor) has a touch switch to auto stop the motor if the lid of the thing gets closed. Well that b*stard of switch just died. Took me a while to notice since it depends on the position but definitely having stayed in the same position for 5 years before we moved-in induced metal fatigue and the inside connector doesn't close anymore. So I bought a replacement fan, and will try to fix the other one which has most likely the same problem with a bit of TLC or tape... At least now I know what is the problem.
The new air circulator, but old one was just the same

The new air circulator, but old one was just the same

2024-07-22 - Went secured : moved to HTTPS ... most of the time!
Since the site runs on HTTPS it has a strange error and stops answering after some time. I solved it on other Flask sites running HTTPS with ... expeditive palliative measures. Ok, I just set it to restart every night and solved 95% of the problem. But now this site too being having the same symptom tells me I have to fix it, and have it run behind a real WSGI and Nginx as a reverse proxy. I'll be doing that soon.

Oh and I got my nice GameBoy Clock mini boards. Stole the connector from old "wireless connectors" for GBA. Just have to file a bit the connector to fit a GB Color, and Bob's your uncle as they say down under. Ain't she cute?

2024-07-14 - Went secured : moved to HTTPS!
We went SECURED! Now the site runs on HTTPS! Took me a few hours, which would have been shorter if I wasn't watching Monk (an excellent drama, I recommend) at the same time. Need to add a way to redirect port 80 to 443, will make a small app for that.

2024-06-27 - Geiger counter improvement
Years ago, I bought on ebay a Geiger counter kit, which was fun to build and works (as far as I can say). Apparently except the bip bip you can use the CPM (Counts Per Minute) to get some sense of the dangerosity. Not needed but why not?
Also made a sample MiniPOC board for Gameboy Link that has no RTC but emulates it. You can plug it directly in the GBA/GBC without cable and no need for extra power!

2024-06-09 - Atomic Clock keeping time
Trying to figure out how to use the pulse from the Rubidium Standard in my Atomic Clock Revisited. Assuming pulse is regular and as close as can be of "real" time (assume pulse is 1Hz makes it 1 pulse = 1 second).
I know when I get the pulse, I can even know what time it was when I get the 1st pulse on wake-up but ... what was the time? How much delta do I have between the real time and the time the uC considers? How can I not make it worse while still saving time once in a while (by updating the RTC). Here's an attempt.

2024-06-06 - Atomic Clock display
Atomic Clock Revisited: I worked on a wallnut board to hold the components, now I need to "show" the time. I wanted to use Tiny Numitron tubes, but they are scarce, and it would have taken me some time to build another one from zero, when a friend of mine who leaves Japan proposed to give me back one clock I made for him a decade (!!) ago. Normally I don't take back presents but since it had become a paperweight for him and I needed it, I decided to accept and recycle her.
A little tinkering and with the MultiClockManager code it ended working after a couple evenings (that was a LONG time I didn't touch these).

So where are we now?
🔲 How to have the RTC work with the incoming pulses? I will cut/lose power, I need to keep the time "as close as possible"... The drift of a DS3234 is already small at about +/- 1 min per year worst case.
🔲 Add also a BCD time display? Useless because of the Numitron but so nicely geeky😻
🔲 Cleanup the power lines, maybe the 7805 can power all in the end?
✅ Scientific package up and running
✅ PPS signal visible
✅ 600MHz signal divided by decade counters (visual effect only)

2024-05-20 - GameBoy Link micro
So I made that Gameboy Clock using the Link port, it's nice but I have to use a cable. I finally found an expensive way to do without: use GBA male connectors from the GBA Wireless module. Just desolder it. With that, I'mm make a minimal version of the board that just has USB connection to make it a GameBoy Serial Terminal.

2024-05-15 - Yet another idea
Hey I could turn a GB in a useless clock, couldn't it also be a GameBoy Serial Terminal for my Linux? Need to try!

Also made an ugly animated gif👇

2024-05-07 - Golden Week 2024 update
Did a few stuff during the GW:

GrblWebStreamer: added the job duration calculation, work area, and display it in the app as well as zoom on the work-area.

Resistor Calculator: I did this during the "golden week", and had some headaches with the float on AVR 8bit, but in the end if works just fine.

2024-04-17 - Side projects
The Atomic Clock Revisited is continuing slowly, and in the meanwhile I did a few things on the side, for a change.

Resistor Calculator a simple calculator where you key in the color bands and get the resistor value

GrblWebStreamer updated to be even more practical and grbl2image Pypi module to convert Gcode to an image got bugfix and improvements (greyscale images support)

ZMQ simple storage is a minimalist solution to push/pop files from a queue in your home NW based on ZeroMQ and with a PyQt5 GUI.

2024-04-15 - Atomic Clock pulsing on gif
Just a small anim to show how it works so far on my bench:

2024-04-14 - Atomic Clock pulsing
Working mainly on my Atomic Clock Revisited: progress continue. I have now the PPS_OUT the 1Hz pulse showed, via a simple NOT gate and a 555 monostable. Yeah, the pulse is 400ns so too fast for human eyes or to give a chance to the LED to blink. And I made a board for that too! Details on the project main page.
400ns pulse

⇨

2024-04-08 - Atomic Clock getting to know each other
Hmmm so on the plus side all works fine: power, the Rubidium standard, the 2 boards I made, the output signals ... On the minus side, I get a 595Hz not a religiously perfect 600Hz. I know the unit needs service but maybe there's a way to address that with the tuning settings? Because 5Hz per sec it's 0.83% error meaning 717 seconds of error per day ! Absolutely unusable as a clock. Even the dollar shop kids watch is way more precise...
Ok then maybe I can say that the clock spits 595Hz and use that value to cadence the sub-systems?
595Hz ain't 600Hz

... and after a little more tinkering, no worries: it's spitting properly 600Hz, it was a precision error from the oscilloscope. If you increase the time resolution you get ~600Hz.
So I went further and did my 2 step power conversion: the 15v is decreased to 7v via a LM2596 board (no heat, little loss, some noise) and then to 5v by the LM7805 (little heat, little loss, close to no noise). This is a big improvement on the loss by heat for now the 7805 is cool even after minutes of usage compared to the barely touchable when he was burning away the 10v he had to drop from 15 to 5. With this I get a bit convoluted and inefficient(?) circuit but I get low heat and clean 5v which were my priorities.
2 stages buck

2024-04-06 - Atomic Clock powered up
Rubidium Standard -Microsemi SA 22c- powered up after I made 2 boards : one for the connector and one for the power. That works and pulses nicely!
See Atomic Clock Revisited.

2024-04-02 - Gameboy Clock (Serial) : it's done
I checked my memo on this present blog, and that's 10 years ago I had the idea of a Gameboy Clock and started working on it. It took me through SOOOOOOO many detours, learning, discouragement, revenge, ... and now it works. Strangely I feel nearly sad, though of course proud. Not sure this will have any further use than being shown to geek friends who visit home, but hell, that was quite a journey. Not sure to who I should say this but from my heart I want to say "thanks for the challenge, I deeply enjoyed it". On to new adventures?

2024-03-28 - Gameboy Clock (Serial) : tying it all together
All the pieces work separately (so far!), now tying in stuffs nicely together. I'm on the GB side now, and once I have a visually appealing clock program, then I can go back to the PCB and implement the RTC reading. Did that already, should be a breeze but who knows. In the meanwhile, a couple hours of tile design and coding gave me that. Still need a bit more but moving fast (kudos to Copilot who's a valuable partner most of the time).

2024-03-26 - ATmega328pB!
Never really cared for the sub-types of MCU and the letters, since it's usually just power ratings. But nooooooooo 328PB is a different beast, with special ID, not just a drop-in replacement. Fortunately it kinda behaves nicely if you're lucky (I was!) but it comes with a lot more of capabilities! Additional SPI, TWI, etc... See the details here.

2024-03-25 - PCB board for Gameboy Clock arrived
Isn't she a beauty? And (so far as per my tests) everything works flawlessly... hoping I'm not jinxing myself! As a dummy clock it works, so next is switching to the Gameboy for the "game", then will be back to the board to add a REAL RTC (DS1307 on this one), and then maybe USB etc. See all details here: Gameboy Clock (Serial).

2024-03-21 - New design tool, new micro-controller
None of them are new per se, but they are for me. I decided to follow most of the amateur PCB designers and move away from Eagle (with a tear in my eye) because of the support stop in a few years and moved to Kicad v8. Easier than I thought and powerful! Just scratched the surface but happy I took the challenge even if it made making a simple board a lot longer. I will make a small USB gadget to emulate a mouse (and stop my PC to sleep), and to do that I ended up duplicating the Sparkfun AVR Stick. Just an Attiny85 board, here I made my RapideUSB Mini.

2024-03-14 - PCB solder stencil at home
Just got the idea to save a few bucks when ordering PCB to make (simple) stencils at home. Afterall I know how to make my own PCB. So here's my receipe on how to make your own Homemade Solder Stencils.

2024-03-09 - GameBoy Clock communications ready!
Well took me time to get back to it seriously, and the upgraded oscilloscope wasn't enough (it would have been retrospectively!) so I had to run my signal analyzer on a Win7 VM but it worked! A small sign inversion fixed, now can send and read to the GB at leisure. Now the ground work is done: need to enter the coding of the real thing!

Oh and while at it, I made a small Homemade PCB debugger board to help, which helped me improve my technique. Worked like a charm.

2024-03-03 - Stickers
I discovered (!) that you can make stickers for your GB cartridge! I had to make a couple, and with my limited artistic skills they do the job! Special sticker paper for laser printer, worked like a charm. Made a template in Inkscape for future reuse.

2024-02-25 - Homemade PCb with laser engraver
I used my transition day at home and the jetlag to good use to test for the first time Homemade PCBs! Promising results for a first time, I got what I did right and what I did wrong, that can be a solution for SIMPLE boards.

2024-02-15 - GameBoy Clock nearly there
I'm really close to have the RTC to GB communication right. It works now, but I have a synchronization issue so it doesn't work all the time. Pretty close though. Unfortunately this will all have to wait until March for I'll be away on biz trip and then vacation away from my workbench. Hoping to not lose the momentum !
HELLO WOR

2024-02-07 - Power source
To avoid pluging my bench power supply (loud) I made a small power board: a Li-Ion battery from an old laptop, charger/protection module, step up module. Works fine but holly molly the output is noisy, like 1.6v noise P2P! Luckily a little 0.1uF cap that was lying on the desk made it more reasonable (~= 600mV P2P). Remember to use caps to filter high frequency noise!

2024-02-06 - Atomic Clock restarted
So yes I have a problem with clocks. Whatever. Years ago I tried to make an Atomic clock with a Rubidium Standard but I couldn't get it to work.
Now trying again with another Rubidium Standard that seems simpler -Microsemi SA 22c- and that I'm sure works (the auction vendor showed pictures): so let's try again Atomic Clock Revisited.

2024-01-29 - Gameboy Clock restarted
I restarted on that project that originally drove me to GB dev like ... 10 years ago? I side track a lot, I know. So after meeting Maximilien Dagois who works the other side of the street and have common friends with me (check his cool book on GB dev!!), I got the idea to not use a custom cartridge (that will be for next decade) but use a Serial connection or "Game Link" cable. Which allows to read/write data a bit at a time in a serial fashion.
So I pulled a donnor half dead gameboy and an old board with a RTC and an Atmega (WordClock FTW) and ... it didn't work. I spent the week (meaning 4 hours spread over a week) to understand that the DS3231 had a failed soldered pad, fixed it with flux, heat and love, and it's back to life! Now on to the second part: connecting it to the GB serial port. Hardwired for now, I'll snip snip a donnor cable later.
Long story short: progress people!!
Gameboy Clock (Serial)

2024-01-19 - Really had to clean my workbench
Too long I didn't do it, and found a bunch of old Li-ion batteries from wide range of provenance. Some of dead are absolutely dead, like fire-hazard level. Here's a pic for you. Look at that crack on that non-genuine replacement battery for PSP or how cushionny this other battery became...
PS: you know the joke about the guy who cleans his desk and find a perfectly working NDS battery the day after he finished a project about an NDS that had no battery?

2024-01-18 - NDS saved from landfill (sort of)
Bought a bunch of GB (NDS, color, pocket) last year or the year before, never got to fix them till now. Got one which battery was dead, and since the screen had small light issues plus the fact it is a original NDS (who wants them?) then I just had fun repairing it on the cheap and made it a USB-C wired one with a buck converter to emulate the battery. It works!
Repair - Nintendo DS battery-less

2024-01-08 - Cheap Buck converter
I'm fixing some GameBoys, a first generation Nintendo DS to be precise and I'm looking at replacing the defunct battery with step-down (buck) converter. Yes the console would need to be plugged to work, but it doesn't boot without a battery and it's just for a test. I'm playing with a cheap module the MH-MINI-360.

2023-12-03 - RPGDice
Winter pushed me back to my old hobbies (and I'm finally getting over me Baldurs Gate 3 addiction) so I'm productive again. Made a small for the fun GameBoy game: RPGDice. Just rolls 8, 12, 20 faces dices for RPG. Nothing fancy, just a quicky project for the fun. Also changed servers so my good ol' faithful with its 1,008 uptime dates saw its days over.

2023-05-10 - Flask and NginX
Making many apps is fun, but hosting them is a necessity and for the low volume of visite, one shared server will be more than enough. BUT many sites don't like to do that unless they are behind a proxy so let's do that and Setup Flask behind NginX proxy.

2023-05-03 - grbl2image PyPi
For my GrblWebStreamer (the stuff to pilot lasers from a Raspi) I wanted a module to "show" the GRBL content as an image. Though you find many systems doing that on the net, nowhere I could find a way to do that in Python, so I wrote it. It was simpler than expected but now it's done and shared with everyone (opensource etc) so go check grbl2image on PyPi!

2023-04-26 - Prompt
I love the Kali style bash prompt on 2 lines, so I made something similar.

export PS1="╔\[\033[38;5;6m\]\u\[$(tput sgr0)\]@\[$(tput sgr0)\]\[\033[38;5;202m\]\h\[$(tput sgr0)\]-\[$(tput sgr0)\]\[\033[38;5;3m\][\[$(tput sgr0)\]\[\033[38;5;6m\]\w\[$(tput sgr0)\]\[\033[38;5;3m\]]\[$(tput sgr0)\]\n╚═>\[$(tput sgr0)\]\[\033[38;5;14m\]\\$\[$(tput sgr0)\] \[$(tput sgr0)\]"

2023-04-12 - Laser Burner continued 2 and creative spring
So I've been hit again by a creativity surge, and work on (too) many stuffs:

GrblWebStreamer is working fine! Plug it, open your browser, upload the GRBL code and let it do the job while you do something else! Tested on jobs longer than an hour and worked all fine ☺️ Since yesterday I'm even making it message me on Line when job is completed (to be packaged properly)

Laser burner on Linux is working fine, has its own enclosure and fans, just need to make some pictures.

ipCamPy.nocv has progressed, you can see multiple cameras and zoom now. Next will be recording stills for a replay or timelapse, maybe add some movement detection/human/wild life identification? Not my forte that last area but gotta start somewhere.

At work I'm working on making Linux on a stick for curious beginners, so I keep details here

2023-03-29 - Laser Burner continued
Now the laser works fine, enclosed and gives satisfaction. Ok 5W laser ain't much when we talk about cutting so patience and careful trial/error is needed but it is doable. Thing is it means having my laptop stuck to the machine for maybe an hour a time, and the fumes are nocives. Like acrylic: you know it's not good to cut it and smell it.
So I'm making a small headless webservice that runs on a Raspi (Zero W most likely) and you upload your code there, run some quick tests via the web interface, click "Burn" and runaway while magic happens. Spend a few evenings on that last week, it does the job so far (of course security, edge cases are "for later"). Give it a look at GrblWebStreamer.

2023-03-02 - DNS update
Laser Burner setup in progress, now it moves ... one axis only, the other one is stuck ... will get to that. Anyway for memory, this is How to update your DuckDNS dynamic DNS. I think I did that 10 times, never wrote it, always rediscover it, so future me: this is for you.

2023-03-01 - Laser Burner
Still kids, still busy work and still no life, so barely no posts in a year. Anyway I was weak and bought myself a laser burner HTPow P7 M30. I started to make one years ago but never finished: I had a basic X-Y table, and will resume that project one day, but not now.
Long story short, the setup on Linux and beginings aren't easy so I'll share it here for memory: Laser burner on Linux.

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