Design of an embedded on-chip debug support module of a MCU

This paper presents a method of designing an on-chip debug support module based on an 8051 architecture microcontroller. It is implemented by embedding a hardware debug module named on-chip debugger (OCD) into an 8-bit high performance microcontroller. Thus, this MCU can do such debugging work as setting hardware breakpoint, single stepping, monitoring and modifying the internal registers, internal or external memories of the CPU, etc. In the paper, the architecture and implementation of OCD has been presented, which is supported by the simulation results. According to the results, it is proved that the in circuit emulation and debugging aiming at the embedded systems are accomplishable with the help of this OCD module. Furthermore, it won't sacrifice the performance of the MCU