code

okay, i think that this will be the last journal, i learned a lot in the path and i want to say that sorry if my english is bad, my native language is spanish not english and it is a bit bad but i try my best to write it.

and the last changes i made for this are that i added silkscreen,

then i created the code based on the guide and using ChatGPT (ill upgrade it and add all the functions i want to add once the parts arrive, because it’ll be easier to test)

i also made the .bom and uploaed all files to github

created 3d case

i added one extra mounting hole because i think i will need to divide in two parts the 3d model because its size is more than 256 in x axe, and i started creating the 3d case following the hackpad case guide, but with wider borders and with the m3 head inserts below the pcb
and i made two holes for the usb and the jack output

after that i started creating the top plate using maths and the plate from hackpad tutorial

it looks very easy to do but it was harder for me. i’m very bad at 3D design lol.

Ended pcb

First, i organized the switches in a piano configuration. then i routed the PCM5100, LM4810, PAM8403, and the capacitors. after that, I routed the switches and diodes. I deleted unnecessary text, routed the LCD screen, verified everything, and tried to make the pcb compact.

It wasn’t that difficult, but it was time-consuming.

Final schematic

i fixed some errors, deleted the physical switch, organized and verified everything with ERC and Ia, so i think it will work perfectly i also viewed datashets of pam8403, and lm4810 to make sure it is right connected.

ended schematics

changed Pam8304 for Pam0303 and i researched how to connect pins on pam8403 and lm4810, i connected first to two stereo speakers and second one to a 3mm jack and added one switch to switch with output will be used

then i created a pad to navigate on the menu, (now ill change the volume, effects, and octaves from there) and i think the schematic is ended

making schematic

okay i first created the switch matrix with three octaves (6 rows and 7 columns) i wired them to the rasp berry pico

after that i wired the lcd screen(i think ill use a pot with a npn transistor to controll the back light, and i searched how to wire the pcm5100 because in the tutorial they didn't explain how to connect some pins and it took a lot of time

and i added two rotary encoders

research

okay I want do a a three(21 notes and 15 sharp notes) or four(28 notes and 20 sharp notes) octaves syntethizer so it will have 36 or 48 switches, i want it to have built in speaker powered by DIP LM4861 or Pam8304 and one output auxiliar output powered by the LM4810, i also want one slider to change octaves and one for the volume, and i found this library to convert i2s to analog and i think that i can add effects like sustain

https://github.com/elehobica/pico_audio_i2s_32b