# ToGo-Lab FireFly Morse Blinker

**DIY kit**: ATtiny-based Morse blinker. Through-hole. No mains. Simple on purpose.  
**Default license**: [CC-BY-NC-4.0](https://creativecommons.org/licenses/by-nc/4.0/)

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## Intro

This is my “Hello World” hardware project on the new ToGo-Lab server. Years ago I built a tiny Morse throwie: ATtiny + one LED + one resistor, plus firmware. This version adds a supercapacitor and small solar cells. It uses the LED as a light detector, so it only blinks in the dark.

It’s not a throwie anymore. Hang it anywhere with decent light (for charging) and dry conditions and let it blink Morse on its own during night.

Goal: a beginner-friendly DIY kit with clear docs and hackable firmware.


Checkout also the [blog about this project](https://togo-lab.io/)
Suggestions welcome. Open an issue or email [tgohle@togo-lab.io](mailto:tgohle@togo-lab.io).

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## Repo layout
```
0001_FireFly/
├─ KiCad/            # .kicad_pro, schematic, PCB, fabrication outputs
├─ CAD/              # 2D/3D mechanical drawings, panel outlines (if any)
├─ Programm/         # firmware source, hex, Makefiles / Arduino sketches
└─ Documentation/    # assembly guide, quick start, FAQ, photos, BOM CSV
```

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## Hardware
- **MCU**: ATtiny45/85 (internal RC clock, no crystal).  
- **I/O**: 1× LED + series resistor. Unused pins broken out to breadboard-style pads.  
- **Programming**: external ISP programmer via Arduino IDE; PDIP-8 ATtiny45/85 footprint.  
- **Power**: 3V DC (coin cell & & solar cell + supercapacitor with Schottky diodes to extend battery power).  
- **Safety**: low voltage only. Observe polarity.  
- **PCB**: hackable; access to unused ATtiny pins.

> PCB notes: big pads for beginners, clear silks, LED polarity marks, ISP near board edge for pogo-clip.

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## KiCad
- **Version**: 7.x or newer recommended.  
- Open `0001_FireFly/KiCad/ToGo-Lab_FireFly.kicad_pro`.  
- Run ERC/DRC and fix errors before fabrication.  
- Plot: Gerbers + drill. Add a README in `KiCad/fab/` with board thickness, finish, mask color, and min track/space.  
- Optional: panel outline DXF/SVG in `CAD/`.

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## Firmware
Two paths. Use what you like.

### A) Arduino IDE
- Board core: any stable ATtiny45/85 core.  
- Clock: **internal**. No fuse change required for first tests.  
- Programmer: USBasp / AVRISPmkII / Arduino-as-ISP.  
- Open the sketch in `0001_FireFly/Programm/arduino/`.  
- Set message and WPM in `config.h`. Build and **Upload Using Programmer**.  
> Timing: internal RC. Unit may run at 1 MHz (CKDIV8) by default—adjust `F_CPU` or disable CKDIV8.

### B) avr-gcc + make
- Toolchain: `avr-gcc`, `avr-libc`, `avrdude`.  
- `cd 0001_FireFly/Programm/avr/` then `make all` → `firefly.hex`.  
- Flash: `make flash` (edit `PROGRAMMER` and `PORT` in the Makefile).  
- `config.h` holds CPU clock, WPM, brightness.

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## Assembly
- Follow `Documentation/ToGo-Lab_FireFly_Assembly_Guide.md`.  
- First power-up: LED should blink test pattern. If not, recheck polarity and bridges.

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## Test / Bring-up
1. Visual check; no shorts.  
2. Power at 3–5 V. Current < 10 mA idle.  
3. Program firmware over ISP.  
4. Verify Morse timing; adjust WPM in `config.h` if needed.  
5. Optional: measure sleep current.

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## BOM
- `Documentation/ToGo-Lab_FireFly_BOM.csv` is the source of truth.  
- Columns: `Designator,Qty,Manufacturer,MPN,Alt1,Description,Notes`.  
- Keep alternates for LED and MCU. Note lot/date codes in commit messages for production.

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## Files to fabricate
- Gerbers and drill files from `KiCad/fab/` (board house-ready).  
- Project file: `0001_FireFly/KiCad/ToGo-Lab_FireFly.kicad_pro`.

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## Known constraints
- Through-hole only. No reflow.  
- Minimal I/O to keep it beginner-friendly.  
- Low power is nice but optional; optimize after the basic release.

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## Roadmap (tech only)
- v0.1-proto: breadboard + first PCB, single message, speed presets.  
- v1.0: build guide, BOM with alternates, pilot 10 units.  
- v1.1: docs polish, optional brightness setting, minor PCB tweaks.

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## Contributing
PRs and issues welcome. Keep it simple. Reproducible steps beat long essays.  
Photos of your build go in `Documentation/gallery/` with a short caption and license notice.