badge-2025

Repository containing the schematics for the flex PCB badge distributed at ESC{21}.

The schematics are licensed under the CERN OHL S v2 license.

The badge has been designed by Jacopo Franco, that we thank for the effort in making this literal show of force a reality ;)

Special thanks to Kezi, Kowalski, K3lite & Baobots for the efforts spent into debugging & flashing all of them during the camp.

And for going the extra mile and designing a custom case that solves many assembly issues, a very felt thanks to k0bld.

cat_badge.mp4

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Badge Instructions

Assembly

• The badge must be folded into position.
• To keep it fixed, we recommend using UV glue, superglue, or thin double-sided tape.
• Do not solder directly onto the PET substrate — this is very challenging, even with bismuth low-temperature solder.

Flashing

USB communication is not supported — the port is for charging only. To flash the badge the first time, make use of the UART and the power pins as below.

USB-C Connector

• The USB-C must also be folded.
• Align the tab with the solid line located after the resistors.
• With the copper contacts facing outward, insert the connector into a male USB Type-C cable.

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Charging

• There are no LEDs to indicate charging progress. The charger is however guaranteed to fully charge the battery in 2.5h. The battery is fully protected and the charger has multiple overcurrent, overvoltage and temperature protections. It can trickle-charge.
• Battery life is approximately 4h with the "All sides music" profile and the WiFi radio at 8.5dBm.
• An interrupt pin connected to the charger will change state during charging. You will have to implement it yourself.

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Firmware

• The badge ships with the WLED firmware by default.

• • Firmware updates can be done via WLED OTA or the Serial pads.

• To connect:

  1. Connect to the Wi-Fi network:

     SSID: wled-ap  
     Password: wled1234
     

  2. Open the address in your browser:

     4.3.2.1
     

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Pinout

Charger status:       GPIO 10
Battery voltage:      Analog GPIO 3 (divider only enabled when LED MOSFET is ON)
LEDs MOSFET:          GPIO 4
LED data:             GPIO 8
I²C SDA:              GPIO 7
I²C SCL:              GPIO 6
Touch button 1:       GPIO 0
Touch button 2:       GPIO 1

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