These SETO/MOV operations cause a bank switch. Obviously, parts of the code were copied to RAM.   2CFC: MOV  *R0+,R2 2CFE: SETO *R2 2D00: MOV  *R0,R0   2D5C: AI   R1,>6008 2D60: SETO *R1 2D62: ANDI R2,>001F   3634: AI   R0,>6000 3638: SETO @>6034 363C: MOV  *R0+,@>83EE   367C: B  *R11 367E: SETO @>6034 3682: MOV @>83EE,R1   833A: MOV @>0006(R12),R1 833E: MOV *R3,*R3      (bank switch) 8340: