Piplayer

This is my project that focuses on creating a music player out of Raspberry Pi zero 2w and basically other trash I found in my drower. This repo is a list of steps you have to do to get it working, basic schematics of control panel, some helper scripts and commands, and a simple program in C for gpio buttons support. If you like it you can try making your own :)

Currently work in progress, as i need to clean up this README and this repo in general.

used parts list

• Raspberry Pi zero 2w
• Adafriut Mini PITFT 1.3
• Waveshare Li-ion Battery HAT
• PCM5102A DAC (or simmilar)
• DIP switches 2-pole
• Universal doublesided Prototyping Board (3x7 cm)
• Tact Switches
• Slide switches (3 pos and 2 pos)
• Some Generic cables

System Image tweaking

generic tips and steps to prepare operating system as much as possible before.
for this project raspberry pi os was choosen, however after a while i realised it was not the best choice.
maybe one day custom operating system will be prepared with tool like yocto. below actions are performed on your mashine. # indicates, that actions require root privelages.

img download

https://www.raspberrypi.com/software/operating-systems/

img customisation

https://brettweir.com/blog/custom-raspberry-pi-image-no-hardware/

/mnt/boot/firmware/cmdline.txt /mnt/boot/firstrun.sh

chrooting into arm system from x86

usefull link (any distro really): https://wiki.archlinux.org/title/QEMU#Chrooting_into_arm/arm64_environment_from_x86_64

flashing:

flashing image to the sd card

# xzcat 2025-05-13-raspios-bookworm-arm64-lite.img.xz | dd of=/dev/mmcblk0 bs=1M count=10240 status=progress

creating new partition for music files

this step is technically optional, however it helps me with managing my music library.

shrink fs as much as possible:

# e2fsck -f /dev/mmcblk0p2 && resize2fs -M /dev/mmcblk0p2

(optional) check storage pace:

# dust /mnt

changing partition table:

if you know what you are doing you can use any other tool. I will be using fdisk.

# fdisk /dev/mmcblk0

shrink p2

e 
2 
10G

list to get last sector:

p
Device         Boot  Start      End  Sectors  Size Id Type
/dev/mmcblk0p1        8192   532479   524288  256M  c W95 FAT32 (LBA)
/dev/mmcblk0p2      532480 21503999 20971520   10G 83 Linux

create new partition

n 
p 
<return>
2150400
<return>

(optional) list to verify everyting worked as intended:

p
Device         Boot    Start      End  Sectors  Size Id Type
/dev/mmcblk0p1          8192   532479   524288  256M  c W95 FAT32 (LBA)
/dev/mmcblk0p2        532480 21503999 20971520   10G 83 Linux
/dev/mmcblk0p3      21504000 62521343 41017344 19.6G 83 Linux

resize filesystem on os partition to full partiton size:

# e2fsck -f /dev/mmcblk0p2 && resize2fs /dev/mmcblk0p2

customisation of raspberry pi os

In this part you modify raspberry pi os. You need access to files, some actions you can perform while mounted, some actions require you having a shell access. Probably the easiest way is to set up the ssh connection to your pi however some .

nonroot user customisation

passwd pi 
usermod -aG sudo pi

create music partition

mkdir /home/pi/music
# echo "PARTUUID=d9c86127-03  /home/pi/music  ext4    defaults 1 2" >> /mnt/etc/fstab 
# mkfs.ext4 /dev/mmcblk0p3

upgrade and update

sudo apt-get -y update && sudo apt-get -y upgrade

https://www.instructables.com/Raspberry-Pi-HQ-Audio-PCM5102-and-MPD/

blacklisting module

sudo vim /etc/modprobe.d/alsa-blacklist.conf

add: blacklist snd_bcm2835

add driver support

sudo vim /boot/firmware/config.txt

comment out dtparam=audio=on (# in col 0) add dtoverlay=hifiberry-dac at the end

sound configuration

modify /etc/asound.conf file:

sudo vim /etc/asound.conf

add below lines:

pcm.!default {
type hw
card 0
}

ctl.!default {
type hw
card 0
}

add self to audio group:

sudo usermod -aG audio pi

reboot:

sudo reboot now

stuff should work by now, test with following commands:

aplay -l
speaker-test -D default -c 2 -twav

https://www.raspberrypi-spy.co.uk/2019/06/using-a-usb-audio-device-with-the-raspberry-pi/ sudo vim /usr/share/alsa/alsa.conf

defaults.ctl.card 1
defaults.pcm.card 1

https://www.hifiberry.com/docs/software/configuring-linux-3-18-x/

https://blog.himbeer.me/2018/12/27/how-to-connect-a-pcm5102-i2s-dac-to-your-raspberry-pi/

bluetooth

bluetooth is optional. https://forums.raspberrypi.com/viewtopic.php?t=306920 https://wiretuts.com/connecting-bluetooth-audio-device-to-raspberry-pi/ sudo usermod -aG bluetooth pi sudo apt install pi-bluetooth bluez pulseaudio pulseaudio-module-bluetooth sudo apt-get install pulseaudio*

https://unix.stackexchange.com/questions/705326/debian-11-bluetooth-sap-driver-initialization-failed https://raspberrypi.stackexchange.com/questions/67617/bluetoothctl-fails-to-connect-to-any-device-failed-to-connect-org-bluez-erro https://askubuntu.com/questions/689281/pulseaudio-can-not-load-bluetooth-module/689297#689297

sudo apt install bluetooth pulseaudio* ~pulseaudio-module-bluetooth~

adafriut Mini PITFT 1.3

getting display working.
usefull links: (pinout of display)[https://learn.adafruit.com/adafruit-mini-pitft-135x240-color-tft-add-on-for-raspberry-pi?view=all] (install instructions)[https://learn.adafruit.com/adafruit-mini-pitft-135x240-color-tft-add-on-for-raspberry-pi/1-3-240x240-kernel-module-install] (driver repo)[https://github.com/adafruit/Raspberry-Pi-Installer-Scripts]

update and upgrade

sudo apt update -y && sudo apt-get update -y && sudo apt-get upgrade -y

Setup Virtual Environment

sudo apt install python3-venv
python -m venv env --system-site-packages

To activate the virtual environment:

source env/bin/activate

sudo shutdown -h now Remove power and attach the miniPiTFT. Watch that the pins plug into the first 2x12 headers! The rounded corner and mounting hole should line up.

Attach power to the Pi and re-log in. The PiTFT should be lit but nothing on the screen. Run the following at the terminal

cd ~
pip3 install --upgrade adafruit-python-shell click
sudo apt-get install -y git
git clone https://github.com/adafruit/Raspberry-Pi-Installer-Scripts.git
cd Raspberry-Pi-Installer-Scripts
sudo -E env PATH=$PATH python3 adafruit-pitft.py --display=st7789_240x240 --rotation=3 --install-type=console

---

installing and configuration of mpd and ncmpcpp

sudo apt-get install mpd ncmpcpp
systemctl --user ebable mpd

controls

All gpio buttons emulate some keyboard buttons, depending on current layer selection

input emulation

huge saver: (input-emulator)[https://github.com/tio/input-emulator], needs modification to support any different keyboard layout than dk, or changing keybord layout and keybinds. linux input emulation (example)[https://github.com/torvalds/linux/blob/v4.12/include/uapi/linux/input-event-codes.h#L64] on github

pigpio

you need to install (pigpio)[https://abyz.me.uk/rpi/pigpio/cif.html] library to use controls wrapper program for gpio buttons.

sudo apt install pigpio

building programs

main build gcc command:

gcc -Wall -pthread -o prog prog.c -lpigpio -lrt

building helper script:

#!/bin/bash

filename=$(basename -- "$1")
filename=${filename%.*}
echo $filename
gcc -Wall -pthread -o $filename $1 -lpigpio -lrt

main program is being executed from .bashrc at home dir.

optimalisations for battery life

turning off unused stuff

https://ohyaan.github.io/tips/raspberry_pi_boot_time_optimization__complete_performance_guide/#2-kernel-command-line-optimization https://www.cnx-software.com/2021/12/09/raspberry-pi-zero-2-w-power-consumption/

config.txt modifications

# Restricting GPU
gpu_mem=16
# Turning off loading overlays for camera
camera_auto_detect=0
# Turning off loading overlays for dsi displys
display_auto_detect=0
# Disabling onboard audio
dtparam=audio=off
# (Comment out) force legacy drivers
#dtoverlay=vc4-kms-v3d

usefull commands i found (didn't feel like doing those)

turning off hdmi https://forums.raspberrypi.com/viewtopic.php?t=113602

/usr/bin/tvservice -o

turning off leds

echo none | sudo tee /sys/class/leds/led0/trigger