Store HALT codes
Yes. Register 8107 is a pointer register to a 16 register stack. If a value is entered in this register, the controller will use that register as the start of a stack of a 16 long stack of the last error codes contained in 8175 (i.e. if a value of 100 is placed in 8107, Registers S100-S115 will contain the last 16 HALT codes generated by the controller).