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+# Byseekel
+
+2023-07-04
+
+## Foreword
+
+This blogpost will be a disappointment. A recollection of wasted efforts,
+a mausoleum of failed designs, a journal of regrettable choices, and
+a maker's acceptance of defeat.
+
+Oh, and it won't be proofread.
+
+Last year, I began building a draft of this blogpost, but never finished
+nor published. It was timestamped 2022-05-03. I wish I could write this
+one in the same cheerful tone, but I can't.
+
+The project started in December 2021. It was finished in July 2023.
+A rational question to ask is:
+
+__What the fuck happened??__
+
+## Bikeblinkers: a recap
+
+In September 2021 I broke my wrist in a cycling accident. It gave me an
+irrational obsession for cycling safety. So I designed this.
+
+![A pair of PCB-form blinkers in a plastic bottle, mounted at the rear of
+a bike. One of them is blinking.](img/byseekel/bikeblinkers.jpg)
+
+▲ This is the only photo I have.
+
+It's basically just a 555 timer in astable mode. Two design errors were
+made:
+
+- The switch is on the path to the LEDs, not the 555, so the chip is
+  always consuming power
+- The transistors are in common-collector mode, so they aren't bright
+  enough
+
+__I was not satisfied.__
+
+## Byseekel rev 0, 1, and 2
+
+December 2021, I went back home with all the Bikeblinker stuff. Finally
+I had time to make something better.
+
+I wanted a whole bunch more features, including
+
+- speedometer and odometer, using reed switch and wheel-mounted magnet
+- hazard light
+- braking indicator
+- remote-activated buzzer
+- an LCD display
+
+At that point, every one of these seemed possible. I smugly named the
+project "Byseekel" because that's how I hear Freddie sing "Bicycle race".
+
+Rev 0 is on perfboard. I don't even remember how painful it was to solder.
+Nevertheless, it worked. Photo on 2022-01-01.
+
+![Two perfboards with messy wiring](img/byseekel/rev0_back.jpg)
+
+▲ I don't know why I needed three voltage boosters.
+
+🎖️ Achievement made: spaghetti wires
+
+![Same two perfboards, front side up](img/byseekel/rev0.jpg)
+
+I used two microcontrollers (MCUs), because I didn't know how to reliably
+switch in and out of sleep mode. The smaller one is an ATmega ATtiny13A
+
+The LCD was intended to go on the handlebar. It was driven with a 4-bit
+parallel interface. I wrote the driver myself with the datasheet, so I was
+very proud. (It was very glitchy, though)
+
+🎖️ Achievement made: First LCD driver
+
+Starting from Rev 1, I gave in and just made PCBs. This one's taken
+2023-01-12.
+
+![PCB with a freshly soldered chip](img/byseekel/rev1.jpg)
+
+▲ I was proud of being able to solder SMT, but it wasn't a good idea.
+
+🎖️ Achievement made: First functioning SMT chip
+
+This board is basically just a single chip and many connectors and
+jumpers. These include
+
+- J1: barrel jack, but instead of 9 or 12, it's 5 volts
+- J2: SPI, to flash firmware into the chip
+- J3: an Ethernet port because I need exactly 8 wires (genius moment)
+- J4: screw connectors
+- J5: controls array of 4 relays to turn blinkers on and off
+- JP1: a jumper to disable the relays before programming, because they
+  share wires, and if I don't pull it out the relay goes "click clack"
+  nonstop
+- J6: I thought it'd be cool if I had a few "hackable" pins for future use
+- U2: radio receiver unit
+
+But I fucked up. It's impossible to install U2 and J3 at the same time,
+because U2 is wider than printed on the PCB. I had completely forgotten.
+
+Fixed in Rev 2. The only photo, 2023-01-18.
+
+![Soldered and wired PCB](img/byseekel/rev2.jpg)
+
+Also, in Rev 1 I forgot I needed a receptacle for the Ethernet cable. So
+I put that in Rev 2.
+
+![Rendering of a PCB with a breakout board](img/byseekel/rev2_jdb.png)
+
+▲ I didn't use mousebites so JDB did not charge me extra. I used a handsaw
+to break them apart. Would not do again.
+
+The main problem with Rev 0 to 2 is the relay. Though they make
+a satisfying noise, they are way too power hungry for a battery powered
+device.
+
+__I was not satisfied.__
+
+## Rev 3
+
+There are too many flaws with Rev 2. I decided to revamp the design
+completely.
+
+Problem: The relay is too power hungry.  
+Solution: Use transistors.
+
+Problem: I can no longer afford more SMT MCUs.  
+Solution: Use DIP.
+
+Problem: I want a marquee-style blinker.  
+Solution: 5 outputs instead of 2.
+
+Problem: 4-bit parallel interface is unstable and wastes wires.  
+Solution: I2C.
+
+Let's begin by introducing designs I didn't throw away.
+
+### Controller board
+
+I intentionally made it credit-card sized. This was in March 2022.
+
+![Front and back of PCB](img/byseekel/rev3.jpg)
+
+### Stalks
+
+![A pair of stalks. One has exposed leads](img/byseekel/stalks.jpg)
+
+Blinker stalks for electric motorbikes. They're very cheap. You just pull
+the lever to the left or right, or both to get hazard lights. Press down
+to reset.
+
+### LED strips
+
+Planned red for brakes also, but now only yellow for blinkers. Scraped off
+some epoxy and soldered wires to the common anode and five cathodes. The
+voltage booster converts 5V to 12V.
+
+![The end of an unsoldered LED strip](img/byseekel/led_strip.jpg)
+
+▲ Then I sealed it in transparent heat shrink tube for waterproof. 
+
+### Radio module
+
+433MHz OOK radio receiver, controlled with a garage door remote. Can store
+and respond to four keys. Currently assigned three to:
+
+- Lock (beep-beep, goes to sleep mode)
+- FindMyBike™ (long beep)
+- FindMyBike™ Silent Mode (flash blinkers)
+
+### Buzzer
+
+It's just a piezo with two LEDs. It beeps when you give it 12V.
+
+![Anatomical view of buzzer](img/byseekel/buzzer.jpg)
+
+### Ethernet cable
+
+In my original design I needed a bundle of eight wires that runs the
+entire length of my bike. An ethernet cable is a bundle of eight wires.
+Genius idea.
+
+Now that I only need three, it's still a genius idea because it's cheap
+and so much easier to organize than three speaker wires.
+
+Now, we'll move on to designs that failed.
+
+## Failed designs
+
+Don't ask a Shanghainese what happened in 2022.
+
+Anyway, I stayed at home from March to June, without access to my bicycle
+or stuff like oscilloscopes. So many ideas worked on my workbench, but
+couldn't be tested.
+
+![Line sketch of two boards. Stemming from controller board: power bank,
+blinkers, braking lights, buzzer, reed. In between: ethernet cable.
+Control panel board: ctrl, stalk, LCD, brake](img/byseekel/feature_creep.png)
+
+In the end, they grew so complicated I had to throw them away.
+
+![braking lights, reed, ctrl, LCD, brake and the control panel are crossed
+out](img/byseekel/feature_creep_removal.png)
+
+### Speedometer & odometer
+
+My uni has a required 80km of jogging per semester, tracked by GPS to
+ensure you're neither too fast or too slow. We cheat it by cycling. Based
+on my knowledge, I can stick a magnet to the spoke of the wheel, and mount
+a reed switch somewhere so each time the magnet passes, we know the wheel
+made one turn.
+
+Problem is, it was winter break, and my bike wasn't home. So to test the
+mechanism, I just held the magnet in my hand and went "whoosh whoosh
+whoosh".
+
+Did it work? On paper, yes. In practice? Probably not.
+
+Then why did I attempt anyway? Perhaps it's because I hate jogging so
+much. My superinflated maker ego was like, "Company xxx made this so
+I must also be able to." Wrong. There are limits as to what one person can
+do at home, even if it "sounds possible".
+
+Right now, 80km is no longer a requirement for me, so I just dropped the
+idea, along with the LCD and control panel.
+
+### LCD
+
+It's a pity I cut it out. It almost worked.
+
+The LCD would serve as a HUD for:
+
+- speed in km/h and min/km
+- trip and total mileage (stored in EEPROM)
+- status of blinkers, brake, and hazard light
+
+I bought an I2C-to-4-bit adaptor board, and rewrote my driver (based on
+[Sovichea Tep's TWI driver](https://github.com/Sovichea/avr-i2c-library)).
+
+🎖️ Achievement made: First I2C LCD driver
+
+The LCD was less glitchy than in parallel mode. In parallel, when the GPIO
+switched, the voltage overshot before it damped down. Thanks to Kliment,
+I learned this was called ringing. But the dedicated circuitry for I2C
+damps harder, so there's less of this problem.
+
+Less, not none though.
+
+### Control panel
+
+One of the ideas that seem good on paper.
+
+![CAD rendering. A stack of boards with parts sandwiched
+in.](img/byseekel/panel_freecad.png)
+
+▲ Made with FreeCAD.
+
+Sometimes, you just feel too confident. You think you're a god. You think
+you can do anything, including mechanical engineering.
+
+The intention is to laser cut eight pieces of acrylic, and bolt them
+together. All seemed perfect.
+
+![Laser cut contours](img/byseekel/panel_laser.png)
+
+In November 2022 I tried to cut them. But the laser cutter didn't like the
+dxf exported from FreeCAD via Inkscape. Each edge was not one line but
+two, so the laser head went over each edge twice. RIP acrylic.
+
+![Acrylic with severely burnt edges](img/byseekel/panel_burnt.jpg)
+
+### Ctrl button
+
+The ctrl button was supposed to switch the HUD when pressed and enter
+sleep mode when held.
+
+### Brake
+
+The brake detection is the single least realistic design I've ever come up
+with. I can't believe how I let it pass. I won't waste time trying to
+explain it again. Here's a figure I drew last year. Go figure.
+
+![](img/byseekel/brakes_idea.png)
+
+## Dormant state and revival
+
+I did practically nothing for the project between October 2022 to March
+2023, because DON'T ASK A SHANGHAINESE WHAT HAPPENED IN 2022. Anyway, in
+April 2023 I found myself motivated once again, partly because there's
+a new hackerspace.
+
+I got this box in 2022. Now I'm finally doing things to it. Horrible,
+horrible things.
+
+![Left: a badly drilled hole on the box. Right: buzzer inserted to said
+hole.](img/byseekel/buzzer_drill.jpg)
+
+▲ I didn't have a suitable grinder, so I just drilled around until the
+small holes formed a big hole.
+
+![Left: the box put vertically in the basket; blinkers taped to basket
+rim. Right: Stalk taped to handlebar.](img/byseekel/basket_mount.jpg)
+
+▲ This made the bicycle difficult to steer, so later I moved the box to
+the back.
+
+## Byseekel, now
+
+What does Byseekel look like, now that I killed every feature I wasn't
+ready for?
+
+We've gone full circle.
+
+Bikeblinkers was blinkers you controlled with a stalk. Right now, Byseekel
+is essentially the same thing.
+
+Except:
+
+- better stalk
+- better wiring
+- powered by MCU
+- marquee
+- FindMyBike™
+- IP-somewhat waterproof
+
+Note that, although there's an ATmega328P, after all the features I killed
+it's essentially the same as your typical Arduino code.
+
+When I have photos and videos, I will post them here.
+
+## Conclusion
+
+Whose fault is it that Byseekel wasn't finished until now?
+
+- It is my fault that I overcomplicated the project
+- It is not my fault that I was locked home for half a year
+
+I am now speaking to future self.
+
+Do you want to add a "useful feature" to a project? You gotta get the
+project working without it first. A new batch of PCBs cost 30 RMB. That's
+cheaper than hours of time you'd waste otherwise. Don't sit on your
+computer, working your ass to make your CAD model "perfect". You can't
+know what's perfect if you never test it.
+
+If I had another chance, I'd kill the brake and reed ideas. The LCD taught
+me to write I2C drivers, and to write AVR C with interrupts; I'd give it
+a pass.
+
+Always remember, do one thing and do it well.
+
+The KiCad and AVR C files for Byseekel and Bikeblinkers are on
+[Codeberg](https://codeberg.org/fkfd/byseekel).
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@@ -8,6 +8,13 @@ MkDocs). But the few that do, are here.
 
 Projects below are sorted reverse chronologically (most recent first).
 
+## [Byseekel](byseekel)
+
+![Both sides of a soldered PCB](img/byseekel/rev3.jpg)
+
+Sequel to [Bikeblinkers](#bikeblinkers), and a cautionary tale of why you
+shouldn't overcomplicate your project.
+
 ## [Reflow Workshop: A Journal](reflow-workshop)
 
 ![Two PCBs with a cat printed on the silkscreen](img/reflow-workshop/kliments_vs_mine.jpg)