About

I'm Pasco. I've worked as an electrical engineer for 25 years, most recently in the semiconductor industry. doer.ee is where I take on independent hardware work and document what I build.

One project, start to finish

Doer USB GPIO, from the first schematic to a boxed product.

  1. Schematic of the Doer USB GPIO with the STM32F070 microcontroller and 40-pin header
    01Schematic
  2. Two-layer PCB layout of the Doer USB GPIO board
    02PCB layout
  3. Unpopulated green PCB panel of Doer USB GPIO boards
    03Bare boards
  4. Assembled Doer USB GPIO board with STM32, CH340 and USB-C connector
    04Assembled board
  5. Finished Doer USB GPIO in a 3D-printed case with a color-coded pinout label
    05In its case
Every stage of the Doer USB GPIO on a cutting mat: an unpopulated PCB panel, assembled boards, printed pinout labels and finished cases

What I do

I design circuits and PCBs in EasyEDA, Altium Designer and Eagle, write firmware for STM32, ESP32 and Silicon Labs EFR32 parts, and bring boards up on my own bench. When a project needs a case, I make it in my workshop with laser cutters, a UV printer and 3D printers, so a prototype arrives as a finished object rather than a bare board.

How I work

I work in writing: proposals, weekly updates with photos and video, and notes you can keep. Decisions stay on record, and you can review progress on your own schedule. Prices are fixed and agreed before work starts.

In the open

Most of what I build for myself is open source, and I write up the details as I go. If you want to see how I work before getting in touch, start with the project build logs, my GitHub or the YouTube channel.

Also from the workshop

The same lasers also make layered wood maps and Chinese paper cuts, which you can find in the shop.

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