Freeform circuits are an interesting style of electronic making that prioritizes artistic expression. Usually electronics projects are designed to keep everything as compact as possible, and the components are hidden away inside of enclosures. Freeform circuits take the complete opposite approach and expose those components in all of their silicon glory. Josef Adamčík has been experimenting with freeform circuits lately, and just finished this impressive freeform ESP8266 OLED MQTT client.
MQTT (Message Queuing Telemetry Transport) is a lightweight messaging protocol designed for embedded devices and other applications where code footprint and bandwidth are limited. The protocol has gained a lot of popularity with IoT (Internet of Things) devices, and so it’s perfect for modules like the ESP8266. Adamčík has already used it for environmental and weather sensors, and so he decided to design an MQTT client that could display the readings from those devices that he has already built.
The freeform circuit that he came up with has an ESP8266 module, a small OLED display, an LED indicator, an FTDI programmer, and a USB power supply. The rest of the components are just what is necessary for those to work properly. To construct the circuit, Adamčík printed out templates that have lines that he could bend the wires to follow. That kept each wire as straight and tidy as possible. With those templates, it was just a matter of carefully lining up the components and soldering them together with precise lengths of wire or thin brass rods. The finished device looks great, and is a great way to view readings from separate MQTT-enabled sensors.