Due to the continuously increasing complexities of embedded electronic systems, there is a clear need for more sophisticated methods of testing and evaluating the performances and reliabilities of the embedded software. One such method is to simulate potentially dangerous events, while monitoring the system’s response and stability. This paper presents a software simulation tool, which will be used for evaluating the mission critical software of the TRISAT mission. The software simulation tool simulates, on a per-cycle basis, the fault tolerant processor and its peripherals while also simulating the effects of the space environment on the simulated hardware. Using the simulation software, a dependability analysis was performed regarding the use of Error Correction and Detection Codes on the processor data memory as well as the rate of memory scrubbing, using two benchmark algorithms: matrix multiplication and quick sort.