Hackers to Hackers Conference

H2HC 2018

A Brazilian H2HC edition represented by a bottle-shaped ESP32 badge with OLED display, BLE behavior, six LEDs, and Arduino-based code documentation.

Sao Paulo · Brazil · 2018

H2HC 2018 Badge

A small-batch H2HC 2018 bottle-shaped PCB badge with an ESP32 WROOM, I2C OLED display, six controllable LEDs, BLE behavior, AAA or USB power, and Arduino IDE source-code notes.

Lifecycle

Add-ons & Upgrades

H2HC 2018 Badge source-backed

firmware feature

BLE message and LED control

The writeup describes BLE write handling that switches LEDs and shows text messages across badge display pages.

Compatibility: H2HC 2018 Badge

H2HC 2018 Badge source-backed

interface feature

OLED display pages

Documented display tabs include main H2HC 2018, dev status, last BLE message, raw debug text, and name pages.

Compatibility: H2HC 2018 Badge

Operational history

Issues & Camp Impact

H2HC 2018 Badge note

missing rights-cleared image · local project policy · needs licensed original replacement

No local H2HC 2018 badge photo has been added because image reuse rights for the public writeup photos have not been cleared.

The catalogue does not copy the writeup photos until image provenance can be represented properly.

H2HC 2018 Badge note

power and programming caveat · primary writeup · documented

The writeup notes BLE battery drain, swapped VCC/GND pins on final OLED displays, and a warning that 12 V serial adapters can fry the badge.

The record documents practical handling and programming risks rather than presenting the badge as a frictionless reference design.

Resources

H2HC 2018 badge writeup project page · Security-Bits writeup documenting bottle-shaped ESP32 badge hardware, OLED, BLE behavior, LEDs, programming, power, and practical warnings.

Sources

Security-Bits.de: H2HC 2018 Badge Retrieved 2026-05-15 · Primary writeup source for ESP32 WROOM, OLED display, BLE behavior, LEDs, power, Arduino workflow, and programming warnings.