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Cache-as-RAM to Bring up Non-Booting Boards

What’s a designer to do when faced with a catch-22? How to diagnose and debug prototype circuit boards that will not boot the bare metal firmware or have no BIOS at all? But without some software, diagnosing structural and functional defects is practically impossible.

One way around this dilemma is to use the processor’s on-chip cache memory instead of on-board RAM to execute diagnostic and test routines. You’ll be able to identify faults like failures in the memory controller, the links to it and many others.