bpi-cm5-hdmi-output-control-8.ino
Script using 'xrandr' and 'fbset' (depending on graphics stack) to force 4K resolution on the main HDMI output.
This script is for Linux with X11 or Wayland desktop environment. It uses xrandr to list and activate HDMI modes. Ensure the HDMI 2.1 cable is connected to the transmitter (Out) port of the BPI-CM5. The Amlogic graphics driver must be correctly loaded.
bpi-cm5-hdmi-output-control-8.ino
#!/bin/bash
# Force 4K HDMI output on Banana Pi BPI-CM5
# Requires: x11-utils, xserver-xorg-video-amlogic (or fbdev fallback)
OUTPUT=$(xrandr | grep " connected" | awk '{print $1}' | head -n 1)
if [ -z "$OUTPUT" ]; then
echo "No active HDMI output found. Check X server connection."
exit 1
fi
echo "Detected Output: $OUTPUT"
echo "Listing available modes for 4K:"
xrandr -q | grep -A 5 "$OUTPUT" | grep "3840x2160"
# Attempt to switch to 4K 60Hz if available
if xrandr -q | grep "$OUTPUT" | grep -q "3840x2160"; then
echo "Switching to 3840x2160..."
xrandr --output $OUTPUT --mode 3840x2160 --rate 60.00
if [ $? -eq 0 ]; then
echo "Successfully switched to 4K."
else
echo "Failed to switch mode. Falling back to 1080p60."
xrandr --output $OUTPUT --mode 1920x1080 --rate 60.00
fi
else
echo "4K mode not found in EDID. Setting 1080p."
xrandr --output $OUTPUT --auto --mode 1920x1080
fi