a pair of in - circuit - emulator modules are embedded within a microprocessor to implement parts of an in - circuit - emulator system . a first in - circuit - emulator module , the in - circuit - emulator memory mapping module , maps specified physical addresses into a debug memory . the physical addresses mapped into the debug memory are set by programmable registers . the second in - circuit - emulator module , the in - circuit - emulator breakpoint module , allows the user to set conditions that cause the processor to recognize specific bus events . the in - circuit - emulator breakpoint module monitors an internal bus and an internal bus controller . the user can set specific bus event conditions by writing to a set of breakpoint registers in the breakpoint module .