Total Time Spent: 20.5h

June 5th: Started Making the base

I have started working on an MP3 player which will also be able to output audio to my Airbuds.

I have selected the ESP32 WROVER as the MCU.

Put an OLED display and SD card reader to it too.

Not sure about them tho still a lot to do

Total time spent: 3hr

June 8th: Edited the schematic a bit

I never used a microSD card with any microcontroller before so I was confused as how to wire the pins to my ESP32. I finally figured it out and wired them up. I also added 4 male jumper pins so that I can easily use a USB to

TTL converter or my arduino nano to flash new codes on the ESP32.

PCB looks like this now

Total time spent: 1hr

June 9th: Added voltage converter

The ESP32 runs on 3.3v but most of the batteries we find like the 18650 li-ion batteries all have a voltage range of 3.7-4.2 which is not safe for the ESP32 so I desided to include a AMS1117 LDO to limit the voltage to 3.3v. I also put a JST connector to connect the battery to the PCB.

Total time spent: 2hr

June 11th: Added extra switch and tidied up the schematic

Thought I need some more switches for the MP3 player. So added 2 more switches.

Gonna start working on the case now.

Total time spent: 0.5hr

June 13th: Changed switch model and added voltage reading

I want to also see how much charge is left on the battery, so I added 2 resistors to step down the voltage which esp32 can read safely Also Changed the switch models

Total time spent: 0.5hr

June 18th: Finalizing the case

Got some free time today to become Good in CAD. I still have to figure out where to put the battery tho

Total time spent: 1.5hr

June 20th: Big Changes

I have decided to also include a GY-PCM5102 module for audio output so I have to change many things. I have also changed the case design to be more compact Placed the Charging and Audio out Module till now Have to put the power button now

Also Changed the PCB

Total time spent: 2hr

June 21th: Big Changes

Changed the Battery Charging module for an adafruit bq25185 charging module as it has both charging and 3v3 output. Removed AMS1117 and battery percentage function from the PCB Made space for the new module in Case.

Total time spent: 2.5hr

June 23th: WHY AM I DOING THIS?

I have exams tomorrow and yet I am making the case I completed the case (Looks Like I am gonna change it again ngl) and made an exploding animation of it!

https://github.com/user-attachments/assets/a201ade8-0bba-4978-ab63-54ee87a1c3f5

Total time spent: 1.5hr