Detection and Isolation of permanent faults in FPGAs with remote access

Abstract

In this paper, we present a Fault Detection (FD) and Fault Isolation (FI) concept for permanent faults in SRAM-based FPGAs. Harsh environments, such as space, cause permanent faults, which results in defective hardware. Furthermore, physical inaccessible systems in such environments limit debugging capabilities. The proposed concept uses wireless remote debugging to access the remote device. The presumption of a permanent fault starts an extended hardware debugging procedure by performing off-line tests without user application. First, the FD process confirms the fault as permanent and reject temporary faults (known as static and transient). Afterwards, a fine-grain permanent FD and FI determines affected primitives in the FPGA and exclude this primitive from the FPGA design. This is realized with a customized recovery strategy for each primitive type, by blocking and bypassing these defective primitives. Focus of this paper is the feasibility of the concept.