nicebadge/README.md

# NiceBadge

**NiceBadge** is an electronic conference badge and a hands-on platform for learning [TinyGo](https://tinygo.org/) programming.

Whether you are attending a conference or just getting started with embedded development, NiceBadge gives you a real piece of hardware to hack on, complete with a ready-to-use firmware, step-by-step tutorials, and progressively more advanced examples that unlock every capability of the board.



---

![NiceBadge PCB render](assets/pcb1.png)

## Features

| Peripheral | Details |
|---|---|
| Color display | Compact full-color screen (FJ08K-S), ST7789 driver |
| Buttons | 2 Cherry MX hot-swap mechanical switches |
| Joystick | Alps EC11E rotary encoder with push switch |
| RGB LEDs | 2 × SK6812MINI-E addressable LEDs, WS2812 driver |
| StemmQT connector | JST SH 4-pin for I2C expansion modules |
| Buzzer | 5.5 mm passive buzzer for audio feedback |
| Bluetooth | BLE via the nRF52840 on the nice!nano |
| USB HID | Acts as a keyboard/mouse over USB thanks to the nice!nano |
| Battery | Onboard battery cell header (2-pin 2.00 mm) |

The microcontroller is the **[nice!nano](https://nicekeyboards.com/nice-nano/)** (nRF52840), which is fully supported by TinyGo and exposes both USB HID and Bluetooth HID out of the box.

![NiceBadge PCB circuit](assets/pcb2.png)

## Repository layout

```
nicebadge/
├── hardware/              # KiCad PCB design files
│   └── PCB-kicad/
│       └── production/    # Gerbers, BOM, pick-and-place files
└── tutorial/              # TinyGo tutorials and examples
    ├── basics/            # Step-by-step basics (step0 → step10)
    ├── ble/               # Bluetooth Low Energy examples
    └── examples/          # Standalone examples (sensors, HID, etc.)
```

---

## Firmware

NiceBadge ships two ready-to-use firmwares:

### Demo firmware (conference)

A showcase firmware that demonstrates all badge peripherals — LEDs, display, buttons, joystick, buzzer, and BLE. Ideal for conferences and as a starting point for your own experiments.

Repository: [code.madriguera.me/GoEducation/badges](https://code.madriguera.me/GoEducation/badges)

### HID firmware

Turns the badge into a fully functional USB/Bluetooth keyboard. Built on top of [sago35/keyboards](https://github.com/sago35/keyboards), a TinyGo framework for custom keyboards.

Repository: [github.com/sago35/keyboards](https://github.com/sago35/keyboards)

---

## Getting started

### Prerequisites

- [TinyGo](https://tinygo.org/getting-started/) ≥ 0.32
- [Go](https://go.dev/dl/) ≥ 1.22
- A NiceBadge board (see hardware section below) or a compatible nice!nano dev board

---

## Hardware

All design files are located in [hardware/PCB-kicad/](hardware/PCB-kicad/).
Production files (Gerbers, BOM, positions) ready for fabrication are in [hardware/PCB-kicad/production/](hardware/PCB-kicad/production/).

### Bill of Materials

| Designator | Value / Part | Footprint | Qty |
|---|---|---|---|
| BT1 | Battery Cell | PinHeader 2×01 P2.00 mm Vertical | 1 |
| BZ1 | Buzzer | Buzzer 5.5 mm | 1 |
| DISPLAY1 | Display connector | PinHeader 1×08 P2.54 mm Vertical | 1 |
| H1, H2, H3, H4 | Mounting Hole | M2 | 4 |
| LED1, LED2 | YS-SK6812MINI-E | SK6812MINI-E | 2 |
| R1, R2 | Resistor | Axial DIN0207 L6.3 mm D2.5 mm P10.16 mm | 2 |
| STEMMAQT1 | StemmQT connector | JST SH SM04B-SRSS-TB 1×04 P1.00 mm | 1 |
| SW1, SW2B1 | Push switch | Cherry MX Hot-swap | 2 |
| SW2 | Rotary Encoder + Switch | Alps EC11E Vertical H20 mm | 1 |
| SW2B, SW2C | Key switch | Strap hole | 2 |
| U1 | nice!nano | nice_nano | 1 |
| U2 | FJ08K-S | FJ08K-S | 1 |

---

## Tutorials & examples

All code lives under [`tutorial/`](tutorial/). Flash any step from inside that directory:

```sh
cd tutorial
tinygo flash -target nicenano ./basics/step0
```

Run `go mod tidy` once inside `tutorial/` to fetch all dependencies.

---

### Basics

A progressive series that introduces every peripheral one at a time.

| Step | What it does |
|------|--------------|
| [step0](tutorial/basics/step0/) | Blink the built-in LED — verifies the flash toolchain works |
| [step1](tutorial/basics/step1/) | Built-in LED controlled by button A |
| [step2](tutorial/basics/step2/) | WS2812 RGB LEDs alternating red and green |
| [step3](tutorial/basics/step3/) | WS2812 LEDs change color with buttons A, B, and rotary |
| [step3b](tutorial/basics/step3b/) | Rainbow cycle on the LEDs, A/B scroll through the hue |
| [step4](tutorial/basics/step4/) | "Hello Gophers!" text on the display |
| [step5](tutorial/basics/step5/) | Display shows a circle per button; rings appear on press |
| [step6](tutorial/basics/step6/) | Analog joystick — a dot follows the stick on the display |
| [step7](tutorial/basics/step7/) | Rotary encoder — turning cycles LED colors, push resets |
| [step8](tutorial/basics/step8/) | Passive buzzer plays a note per button press |
| [step9](tutorial/basics/step9/) | USB MIDI — badge sends notes C4 / E4 / G4 to any DAW |
| [step10](tutorial/basics/step10/) | USB HID mouse — joystick moves the cursor, A/B click |

---

### BLE

Bluetooth Low Energy examples using the nRF52840 on the nice!nano. Compatible apps: **nRF Connect**, **nRF Toolbox**, **Serial Bluetooth Terminal**, **LightBlue**.

| Step | What it does |
|------|--------------|
| [step1](tutorial/ble/step1/) | **Counter** — advertises as Nordic UART Service (NUS), sends an incrementing counter via BLE notifications every second; display shows connection status and current value; send `reset` from the app to restart the count |
| [step2](tutorial/ble/step2/) | **LED color control** — mobile writes 3 bytes (R, G, B) to a custom characteristic; both WS2812 LEDs and the display update immediately |
| [step3](tutorial/ble/step3/) | **Scanner** — lists nearby BLE devices with name and RSSI, color-coded by signal strength; button A clears the list |

---

### Examples

Standalone, feature-complete programs.

| Example | What it does | Extra hardware |
|---------|--------------|----------------|
| [thermal-camera](tutorial/examples/thermal-camera/) | AMG88xx 8×8 IR sensor upscaled with bilinear interpolation and rendered with an iron-palette color map on the full display | AMG88xx sensor on I2C1 (SDA=P0_17, SCL=P0_20) |
| [rubber-duck](tutorial/examples/rubber-duck/) | USB HID keyboard automation (Ubuntu/GNOME target): opens a text editor, types a message, and launches a URL. Press button A to trigger | — |
| [co2-sensor](tutorial/examples/co2-sensor/) | SCD4x CO2/temperature/humidity sensor: display background turns green/yellow/red by CO2 level, LEDs mirror the color, buzzer warns above 1500 ppm | SCD4x sensor on I2C1 (SDA=P0_17, SCL=P0_20) |

---

## Acknowledgements

NiceBadge is based on the **[conf2025badge](https://github.com/sago35/keyboards/tree/main/conf2025badge)** by [sago35](https://github.com/sago35), which debuted at the TinyGo Conference in Japan. NiceBadge shares the same form-factor and was built on top of the groundwork たかさごさん laid there.

Thank you, for the inspiration, the open design, and all the work that made this possible.

---

## License

See [LICENSE](LICENSE).