Monitor and Capture Output Data of Dot Matrix LCDs with DoMSnif Dot Matrix Sniffer

Every engineer has found themselves needing to export data from one device to another at one time or another, and while some equipment offer options to do so, others have removed that capability from their wares. Australian systems engineer Blair Wyatt ran into such a problem when trying to record the temperature of his BRTRO-420 reflow oven by interfacing with its controller using an inbuilt serial connection.

To get around that issue, Wyatt decided to tap into the oven’s LCD display, take the data, and pipe it over to a phone or laptop where it can be recorded and saved. To that end, he designed the DoMSnif — a Dot Matrix LCD Sniffer Bluetooth adapter, which outputs the data from LCDs to mobile devices.

“If you have a device with a dot matrix LCD such as the KS0107/8 based LCDs and you want to capture the output or monitor it, then the Dot Matrix LCD Sniffer/Decoder Bluetooth Adapter (DoMSnif) is just the thing you need. It will passively monitor the parallel display data from any supported LCD screen and send it via Bluetooth or USB to a device of your choice where it can be decoded or processed.”

Wyatt developed the DoMSnif using an Adafruit nRF52 Feather and logic analyzer, coupled together on a custom adapter board, which allowed him to capture and parse the signals going to the oven’s 128 x 64 screen. The data is then sent via Bluetooth to a mobile device that displays the information using a virtual LCD.

Wyatt’s DoMSnif is still a work in progress, and those interested can follow along with new updates on his project page.