Microprocessor and FPGA interfaces for in-system co-debugging in field programmable hybrid systems

Modern trends in technology require efficient control and processing platforms based on connected software-hardware subsystems. Due to their complexity and size, algorithms implemented on these platforms are difficult to test and verify. When these types of solution are being designed, it is necessary to provide information of the internal values of registers and memories of both the software and hardware during the execution of the complete system. The final architecture of the targeted design and its debugging capabilities strongly depends on how the hybrid system is connected and clocked. This article discusses different architectural strategies that have been adopted for a hybrid hardware-software platform, built ready for debugging, and that uses components that can be easily found with a few special features. All the solutions have been implemented and evaluated using the UNSHADES-2 framework.