Source code of iNap Malinka. The code and only the code is shared under GNU GPL v3.0, due to open source libraries which are used:
If for any reason you want to install fresh system and not use the OS picture I provided, this guide should help you.
The most suitable OS would be RetroPie, although it's possible to install Raspbian or other OS. If you don't want to run custom scripts, you may want to take look at Lakka. In this guide we will use RetroPie as it runs both games and custom scripts, and already has builtin many benefits like RetroArch.
Get an image from here and choose the option for your Pi (probably Zero 2W). Install it on your SD card as you always do, for example with balenaEtcher.
As soon as you installed the system on your SD card, don't insert it in in the RPi yet! Copy two files, ssh (note tha lack of extension) and wpa_supplicant.conf to the boot partition. Remember to change your country, ssid and password as needed!
Insert the card into Pi, and after few minutes it should be visible in your local net (you can either log into your router and see connected devices, or use an IP Scanner). Use any SSH of your choice: PuTTy, Bitvise SSH or Windows builtin SSH. Log in with password "raspberry", and change it if you want. You should see a screen like this:
Do not forget to update your system!
sudo apt-get update
sudo apt-get upgrade
In this file we will activate following things:
- auxiliary SPI with two devices,
- disable main SPI,
- change the right screen resolution
- enable PWM audio
- disable unnecessary things
Open the file with
sudo nano /boot/config.txtor open it manually. (or just skip and copy-paste the file from the repo)
The auxiliary SPI is used for the radio and ADC converter. Add dtoverlay=spi1-2cs and make sure to comment #dtparam=spi=on.
We will use custom SPI driver for that.
Add following lines:
hdmi_force_hotplug=1
hdmi_group=2
hdmi_mode=87
hdmi_cvt=480 320 60 1 0 0 0
First line forces HDMI output even if nothing's connected physically. Second and third line forces "blank" display mode, which we define as 480x320@60fps picture.
Malinka utilizes a similar DAC design as the original Pi does.
gpio=12,13=a0
dtparam=audio=on
audio_pwm_mode=2
dtoverlay=audremap,pins_12_13
disable_audio_dither=1
#enable_audio_dither=1
We tell the system to switch pins 12 and 13 into their PWM modes. We enable (pwm) sound, and disable audio dither to prevent a "hiss" sound: if you feel confident, you can comment "disable" line and activate "enable" line too.
Paste following lines:
force_eeprom_read=0
dtparam=i2c1=on
dtparam=i2c_arm=on
dtoverlay=malinkats
The first line tells Raspberry to not look for any shield eeprom. Then we activate the I2C interface, and we load a custom overlay.
Save with CTRL+S, and exit with CTRL+X. Reboot the system (sudo reboot now) and type in ls /dev/ | grep spi. It should show two SPI devices:
If you type in dmesg | grep ft, you should see a loaded touchscreen driver.
First, clone and configure the code repository:
sudo apt-get install cmake
cd ~
git clone https://github.com/Leoneq/iNapMalinka-code.git
cd iNapMalinka-code/driver
tar zxvf bcm2835-1.66.tar.gz
cd bcm2835-1.66/
patch -p1 < ../bcm2835-1.66-aux-spi.patch
# (Thanks Doug for the patch! https://groups.google.com/g/bcm2835/c/NHbYW9V2vmQ)
./configure
make
sudo make check
sudo make install
cd ..
make
As a result, you will get two executable iles: malinkabtn and malinkabtn-sans, which is a special branch of the driver made just to fight sans.
For the first setup, let's stick with the main malinkabtn, and test it with sudo ./malinkabtn:
Exit with CTRL+C.
I really recommend to use fbcp-ili9341 instead of the old, default fbcp. The author made a really blazing-fast driver, pushing the display to it's limits. To install it, follow the code:
cd ~
git clone https://github.com/juj/fbcp-ili9341.git
cd fbcp-ili9341
mkdir build
cd build
Now, to show a battery overlay, simply put the custom file low_battery.cpp and replace it in the source folder. Build the driver:
cp ~/iNapMalinka-code/fbcp-ili9341/low_battery.cpp ~/fbcp-ili9341/low_battery.cpp
cmake -DILI9488=ON -DGPIO_TFT_DATA_CONTROL=24 -DGPIO_TFT_RESET_PIN=25 -DGPIO_TFT_BACKLIGHT=26 -DBACKLIGHT_CONTROL=ON -DSTATISTICS=0 -DSPI_BUS_CLOCK_DIVISOR=10 -DDISPLAY_CROPPED_INSTEAD_OF_SCALING=ON ..
make -j
and you can test if it works, by running sudo ./fbcp-ili9341. If the screen flickers or shows artifacts, change the DSPI_BUS_CLOCK_DIVISOR=10 to higher values, but remember that it must be an even number. More info in the main repo.
The screen driver and joystick driver must load at every boot of the system automatically. You can either leave the executable files in their folders, or make a new folder, move them and delete the source files.
mkdir ~/drivers
cp /home/pi/fbcp-ili9341/build/fbcp-ili9341 /home/pi/drivers/fbcp-ili9341
cp /home/pi/iNapMalinka-code/driver/malinkabtn /home/pi/drivers/malinkabtn
# OPTIONALLY: this will remove the repositories permanently!
rm -rf /home/pi/fbcp-ili9341
rm -rf /home/pi/iNapMalinka-code
Open the startup file with sudo nano /etc/rc.local and paste following lines:
sudo /home/pi/fbcp-ili9341/build/fbcp-ili9341 &
sudo /home/pi/iNapMalinka-code/driver/malinkabtn &
There are two ways in RetroPie to run custom scripts. Your .sh file can be put directly into ~/RetroPie/retropiemenu to show as a script, or you can make your own emulationstation 'system'. Open the ES systems file with sudo nano /etc/emulationstation/es_systems.cfg and add the following system:
<system>
<name>apps</name>
<fullname>Applications</fullname>
<path>/home/pi/RetroPie/roms/apps</path>
<extension>.sh .SH</extension>
<command>sudo /home/pi/RetroPie/roms/apps/%BASENAME%.sh</command>
<platform>default</platform>
<theme>default</theme>
</system>
Now, you can put your .sh scripts into /home/pi/RetroPie/roms/apps even through Samba!
To run graphical applications (that utilizes touchscreen, and colorful LCD) instead of normal console apps, you will need an X server. You can install it with sudo apt-get install xserver-xorg and run with Xorg -config /etc/X11/X.conf :3 - but remember that this is just the X server, so you don't have even a window manager and other "x" stuff. But this is just enough for running embedded applications! Take a look at the example script to see how I did a GUI application.
This step isn't necessary but 256MB of ram isn't really much for C compiling, if one was about to build i. e. Xash3D or other emu from source.
sudo dphys-swapfile swapoff
sudo nano /etc/dphys-swapfile
Change the CONF_SWAPSIZE to higher value, such as 512MB or 1024MB (remember that higher values may shorten the life od SD card significantly)
sudo dphys-swapfile setup
sudo dphys-swapfile swapon
Go to raspi-config and select headphones as the default audio device (System options > Audio > Headphones)
And then sudo reboot now.
In order to improve the audio output, you may want to enable the audio equalizer. Install the alsa plugin with sudo apt-get install -y libasound2-plugin-equal, and edit the setting file sudo nano ~/.asoundrc - paste following content (assuming that headphones are device nr. 1)
pcm.!default {
type plug
slave.pcm plugequal;
}
ctl.!default {
type hw card 1
}
ctl.equal {
type equal;
}
pcm.plugequal {
type equal;
slave.pcm "plughw:1,0";
}
pcm.equal {
type plug;
slave.pcm plugequal;
}
And reload the alsa with alsactl kill rescan. You can play an example sound with speaker-test -t sine -f 400, or speaker-test -t wav -c 6 to play sine wave or a voice clip respectively. Alternatively, run a game in the background while adjusting the audio properties. Open the equalizer with alsamixer -D equal. A proposed configuration:
(needs cleaning!)
dtc -@ -I dts -O dtb -o malinkats.dtbo malinkats.dts
sudo cp malinkats.dtbo /boot/overlays/malinkats.dtbo
sudo apt-get install chromium-browser omxplayer libgnome-keyring-common libgnome-keyring0 libnspr4 libnss3 xdg-utils matchbox xorg gconf-service libgconf-2-4 rpi-chromium-mods libwidevinecdm0
echo "hi"
sudo screen -dmS X Xorg -config /etc/X11/X.conf -nocursor :3
export DISPLAY=:3
chromium-browser --kiosk --app=https://jcw87.github.io/c2-sans-fight/ --start-fullscreen
cd ~
git clone https://github.com/zerojay/RetroPie-Extra.git
cd RetroPie-Extra/
./install-extras.sh
wget https://raw.githubusercontent.com/Immediate-Mode-UI/Nuklear/master/nuklear.h
sudo apt-get install libglfw3 libglfw3-dev
sudo apt-get install libglew-dev
echo 0 | sudo tee /sys/class/leds/led0/brightness
aplay something.wav
alsamixer
alsamixer -D equal
aplay -l
#lists all audio devices
evtest --grab /dev/input/event0 > /dev/null
The main project found here is licensed under CC BY-NC-SA 4.0!