Uploaded December 2025 | Updated September 2026, 2 weeks ago

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In this video I will show you how to mod your GRS Build-A-cade from using the 4.7" wide screen SPI display to a Waveshare 4" Square display.

items you will need for this project:
Waveshare HDMI 4" Screen - amzn.to/4qgyrlp
Pi 3 HDMI Cable -amzn.to/4qgHaUS
Pi 4 HDMI Cable - amzn.to/4p3vJin
or
The GRS Viper HDMI cable - amzn.to/4p3vJin
or for the GRS Viper / Pi4 - https://a.co/d/eQ4dlDt

Why not get another GRS Build-A-Cade since its 20% off for the 2025 Holiday
thunderstickstudio.com

Get STL Files here:

thingiverse.com/thing:7240739

changes to the normal pi 3 or pi 4 GRS Build-A-Cade OS on the SD card is needed

1. open the config.txt file in the root directory of the TF card, and add the following code at the end of config.txt

dtparam=i2c_arm=on
dtoverlay=waveshare-4dpic-3b
dtoverlay=waveshare-4dpic-4b
dtoverlay=waveshare-4dpic-5b
hdmi_force_hotplug=1
config_hdmi_boost=10
hdmi_group=2
hdmi_mode=87
hdmi_timings=720 0 100 20 100 720 0 20 8 20 0 0 0 60 0 48000000 6
start_x=0
gpu_mem=128


2. through PuTTY or WinSCP type - nano /boot/cmdline.txt
►video=HDMI-A-1:720X720M@60,rotate0

3. through PuTTY or WinSCP type - opt/retropie/configs/all/autostart.sh
►emulationstation --screenrotate 0 --screensize 720 720

4. through PuTTY or WinSCP type - opt/retropie/configs/arcade/retroarch.cfg
►video_allow_rotate = "true"
►video_rotation = "0"

5. new splash screen or use a program to rotate the current one

note for screen rotation
0 is default (portrait), 1 rotates 90° clockwise (landscape), 2 rotates 180° (upside down), and 3 rotates 270° (90° counter-clockwise