i had one mechanical keyboard after getting bored i tried to reverse engineer it but i couldn't send any usb data or i could not see much on the terminal when i tried to see if it listens to the data and after opening i saw that it only takes +5v and gnd plus the processor something like BYK.. was a hard coded chip that doesnt listen notes i was newbie to hardware and really scared to try anything. so i gave up but seeing my brother have a kreo rgb keyboard it gave me some boost to open it up and i learned so much and burnt my hand while trying to solder.

heck i even burnt the solder iron's wire itself (sniff sniff whats that smell). 

so the plane was that i would use a mcu as esp 32 or pico that listen to my command and can do anything that i want .

first month really .... 

i bought a mulitmeter and did the traces of all the rows and col sicne there was no pcb and other design files there i didnt know how keyboard matrix works at all i went rhough whole thing.. after getting all the traces and nothing them i was really soul scattered by the fact how this whole thing worked but then i got to know this was a common thing everyone knew this.

  
after this i took pico as the main mcu why...

1. it was small 

2. it has higher clock speed.

3. it was one sale since the esp was on boom and the price of pico was dropped

4. it has more computer power that i needed for Fourier transform for disco light that i wanted for the custom rgbs i would put there

quickly after that i ran into a problem of less gpio also 

  
after that i took a longer time to solder since i was learning and it was very scarry to solder on the pcb but as i did i grew more confident .. after burning my finger prints.

  
i bought a io expander because of 6 rows and 17 cols it got burnt and again tried that was jittering the one signal was affecting other signal. so i gave up 3-4 cols and went for the gpio full on.

The RGBs... Hardest 

the rgb i had to cut each rgb strip stick them all on each keys then use the single core wired without the cover and solder each joints aroung 300 small pieces of them total 600 joints appx and it was tough because heating one end would make other end heat up also. 

but since i cascaded 100 of them the voltage kept decreasing and it was 0.5v at the end so i just provided supply from both of rows and it worked and there was no deeming and jitters.

thats it... if u want to know about the logic behind it then u can ask me i will add it most of things and testing and all the stuff is in the video

Customizing my Mechanical keyboard using rpi pico