The calibration of @norbim doesn’t work for rotated screens.
My numbers are
205 3754 3801 226
You can do your own calibration:
apt-get install -y xinput-calibrator
Create a file calibrate.sh on the zynthian that contains
#!/bin/sh
xinput_calibrator -v
make it executable
chmod +x calibrate.sh
stop zynthian and run calibrate
systemctl stop zynthian
startx ./calibrate.sh
Follow the screen instructions
In the ssh output where you started startx, you find the calibration values