V3.1.4 - Mass production version, the first batch of mass production firmware V3.1.5 - Mass-produced version, the first batch of mass-produced firmware - mass-produced version, found that the temperature below 0 degrees reading error, the program will run wrong, and modify the relevant issues V3.1.6 - Fixed 1 step non-turning problem, maximum force setting - 1st gear to turn off the out of step alarm, the maximum force V3.1.7 - Increase the load capacity