Debugging Techniques

Although the DDR subsystem eliminates the complexity in DDR SDRAM interface design, debugging memory failures is a challenge. Tracking down functional issues (at the FPGA or system level), functional system interaction problems, system timing issues, and signal fidelity issues between FPGA and memory devices (such as noise, crosstalk, or reflections) becomes much more complex. Care must be taken right from the DDR subsystem configuration phase to the PCB layout phase to achieve the expected performance. This section describes the tools and processes used to debug the DDR subsystem interface.