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Project information

  • Owner: Lomanic
  • Participants: none
  • Status: deployed at Lomanic's office
  • Project created on Sun 14-11-21 by Lomanic


  • Implement Operame, a project from the Dutch hackerspace Revspace using a CO2 sensor coupled to a TTGO T-Display to tell people in a room that they should open the windows to limit Covid-19 aerial spread indoors
  • Document it in English
  • Maybe extend it in some way (automatic ventilation system?)


As I won't order PCBs online (and specific SMD sockets as shown in soldering instructions video) and just use what I have at hand, it will be assembled on a perfboard I had in my drawer for years.

TTGO T-Display pinout, mirrored from


TTGO T-Display      MH-Z19C
   5V                 VCC
   GND                GND
   D26                RX
   D27                TX

D12 on the TTGO has to be grounded but it's not obvious why

Software unmodified, had to install vscode (vscodium doesn't have platformio in its openvsx store) and the appropriate driver on Windows so platformio could flash the TTGO T-Display onboard ESP32

In action

The Operame device is shown mounted on temporary breadboards with bridges made of Dupont wires as a proof of concept

Perfboard implementation, front

Perfboard implementation, back



Initial proof of concept with breadboard, everything works perfectly.

Then perfboard implementation. A first for me, quite the hassle, I probably didn't go the easiest way with the solder traces and then the cables on the back. A multimeter with continuity mode is a must have to ensure there's no short between traces.

Next time, solder traces are not worth the time and headache and cables should just be soldered through holes with a single solder joint to the next hole.


projets/fuz/operame.txt · Last modified: 2023-02-02 22:06 by