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Designing the Board

A project log for IOT Mechanical Clock with Bluetooth App

Big clock from the 90's overhauled to obey an ESP32 instead of its old motherboard. Lots of possibilities for display. Very clicky.

Keenan ReberaKeenan Rebera 12/21/2020 at 20:100 Comments

I had decided to use the MCP port expander in order to control several of these over I2C when I stumbled upon May Fourth's Sig7Seg design on Tindie. I noticed that she was using the TBD62083 in order to drive the digits, but I wanted a better footprint for mine. I wanted to be able to hot-swap and test the units without soldering the wires right to the board and I wanted to make it compatible with the QWIIC ecosystem. So I designed the board, ordered the parts, and got to work cooking them over a hotplate in the backyard.


I noticed there was one wiring error in the board, which I have since updated in the design files. It was trivial to fix, however, so I just soldered small wires onto mine instead of reordering the boards.

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