On-Line Testing and Diagnosis of Microcontroller

This paper presents an on-line testing and diagnosis approach of microcontroller. The proposed approach has been achieved through both fault masking and fault diagnosis algorithms. Concurrent testing technique through using triple modular redundancy (TMR) is required to mask the operational faults and specially tolerate the transient faults. For permanent faults and in parallel with TMR, an on-line and non-concurrent fault detection and diagnostic technique is used to locate the faulty elements. The fault detection and diagnostic technique uses a set of assembly programs that test the entire microcontroller instruction-sets called macros. The macros are able to excite all of the microcontroller functions. A macro is associated to each machine-level instruction; and composed of a few instructions, aimed at activating the target instruction with some operand values representing the macro parameters and propagates the results of its execution to an observable memory positions. A Simulation study has been done using Xilinx Foundation tool, VHDL, and an FPGA Vertix chip.