1/10/2026 10 PM - finished the Schematic

I finished making the schematic following the guide, didn't expect it to take this long.
I did end up confusing myself a few times as to why i had 100nF and 0.1uF caps labeled seperatly.

I also remembered that you could use "ins" on your keyboard to quickly get all the numbers on the GPIO pins done quickly

1/10/2026 11 PM - Choosing components

spent a bit of time picking out components and working out if i needed to change values etc

BIG SHOUT OUT AND THANK YOU TO KAI FOR TELLING ME THAT SWITCHING TO 22 OHM TERMINATION RESISTANCE WILL REDUCE MY COST :yay:

Spent a little bit of time on LCSC looking for a suitable smd mount button
and then a bit more time making a footprint for it so i could actually use it

also realized i needed to actually make pads
not just things on the front copper layer oops

I finished choosing components!

Because I had to pick parts for some of the components this also means some of my BOM stuff is also already done!

1/11/2026 2 AM - making progress routing the traces

wow, i have no idea if I've managed to mess up default key binds, or if im not on the latest version, or what is happening , but getting differential traces to work wasn't fun

still working through the rest of the routing

1/11/2026 3:50 AM - finished routing the PCB

WOOO i finished routing the PCB
this took much longer than expected, but its turned out ok.

DRC comes back pretty clean
nothing major, a few clearance things but, nothing too egregious.

i also ignore these tests

im not the happiest with GPIO3s routing but its fine i guess, i still got good ground for the RP2040 without running too much under it

1/11/2026 3:51 AM - fixed some DRC issues

This was what was causing my DRC issues

I slid that big 0402 SMD component up which then gave me room to wiggle the traces around and get everything to fit.

after a few other bits of wiggling traces all of the clearance errors are gone.

All i have left now is:

• create PCB art
• create BOM
• screen shots of cards before submitting to blueprint
  

1/12/2026 - Made some changes to make it uniquely mine

Here is a photo of the routing now, you would need to have quite a keen eye to spot what i changed from this so i will go through what i changed

i used the previous unused gpio25 to connect a 1 wire temperature sensor
the "Mysentech DS18B20U(MY)"

interestingly you can configure the DS18B20 to power itself from the data line, which is super cool.
Im still going to power it externally, maybe i will experiment with that feature on a different project

I also added a green led onto the VBUS with a resistor to provide a status light.

I also found a source for each on LCSC and added it to the BOM for later

1/20/2026 - made the PCB more fun

finished the last few touches by adding Heidi and a complimentary lemon

Spent a while trying to get the lemon and Heidi's eyes to have the copper/soldermask eyes

At first I was just trying to edit the layer in kicad normally.
Then i started trying to vectorize the image before adding it to Kicad.
I started trying to edit a .kicad_mod file to try change something there

It was much easier than that :pf:

In the end I need to edit the footprint in kicad

Then for each part I wanted to show, I needed to turn on solder mask

I worked it out in the end after a while, quite a while