Creality CR-30 Belt Printer.
This repository contains a firmware version for the CR-30 that will allow for a Negative Y-axis Offset and also has the new M808 looping feature.
Disclaimer:
This is a Beta version and as such there may be yet undiscovered bugs. Presently I am running this on my CR-30 with no functional issues.
Once Creality shares the original firmware file I will add it on here for anyone wishing to revert to factory firmware..