Ordered Parts, Assembled, and Tested

MicroDev128 Project

Quick recap:

I like the Arduino Nano but wow is it old. And outdated. And slow. And underpowered. So I put all my frustrations into making a board the same size (’cause trying to use a ESP32 on breadboard sucks when they are so thick) and waayyyyyyy more powerful. So then this thing was born. With a power regulator that can supply two times more current that my oscilloscope draws , mixed with the latest and greatest 8-bit AVR microcontrollers (not that 8-bit AVR microcontrollers are very new).

Sorry I haven’t devloged in a while so this is a lot of stuff in this devlog. This will say 1h 4min logged [because im really bad at remebering to devlog and I use my phone often that I can put Lookout on so I someone gets in the recordering I have to trash it :( ]

Day 1

I started by ordering parts from Digikey. I spend roughly 3 hours looking at part selections for the passives and LEDs.

Day 2

After the parts arrived I looked through the parts and then assebled one board. The caps placement was tricky because they all look the same size, so I’ll add a diagram to the Github repo in the future to make this easier.

Day 3

I tested the board and, well you can watch the video to see how it turned out.

So thats this updates devlog. See the Github repository for more info: github.com/ILikeBWRs/MicroDev128

WATCH THE VIDEO

Cleaning Up the PCB and getting it ready for production

Woooooo!!!!!!!!!!!!!!!!!!
Its done

Check the other MicroDev128-32P devlogs for more info.

I changed the short circuit/reverse polarity protection to using a TVS and fuse. I fixed some errors, worked on docs, and finished doing the silkscreen labels. Now I have to request funding and test (aka abuse it until it blows up >:] )
Sorry for gaps in the time-lapse, I got distracted reading my voltage regulator datasheet and forgot to pause the recording. Maaa Bad.

PCB Routing Pt3

Finally Finished Routing the project!!!!!!

Took a while but I ended up using layer 3 as a mixed power and signal plane insteed of a solid power plane. I am happy with how it turned out. I still might add TX and RX lines to the UPDI header, so you can do serial print.
Overall very happy. Now I have to finish the silkscreen labels, do the documentation :/ , and test it (yay).

PCB Routing
MicroDev128-32

Started routing everything for the whole board. I am sick of routing a good seeming line and then ripping it up 20 times.

• Started on the power lines
• Made planes for the GND and 5v lines
• Learnt that I really suck at PCB design in general

________________________________________________________________Project Overview

Based on the AVR128DB32, with the LT8653S switching power regulator. It has:

• Up to 2 amps on both the 3.3v and 5v lines.
• 128kB Flash and 16kB SRAM
• MVIO on 4-pins with 3.3v, 5v and EXTERNAL source presets
• UPDI Programing
• Arduino Nano sized footprint
• Aims to have a better price to performance ratio than
  Arduino (not hard considering a Genuine Uno is $40 NZD (About 20 USD)

More to come as I hopfully soon finish this project!

PCB PT2

This time:
I have changed the voltage regulator to be the LT8653S (smaller footprint)
I have relaid the board (again)
I have started routing some basic data lines and the crystal.
I have updated all footprints

More to go!
Getting there

Schematic Finishing and PCB (PT1)

Schematic PT2

Schematic AND ideas

Schematic Work and Pondering

Hardware figuring out

Block Diagram

A basic program “BLINK” for the bare chip I have.