• Journal of the Institute of Electronics Engineers of Korea SC
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• v.48 no.5
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• pp.66-73
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• 2011

I try to solve the problem of the usage of the general software interrupt with the nested call of the software interrupt and the effective passing way of the parameters. The software interrupt should be protected against the indiscriminate access because it is used to call the system functions or to use the system resources by generating a software interrupt. But, it is difficult to effectively handle the SWI instruction because of its limited usage. I designed and implemented nested call of the software interrupt and the effective way that handle the parameters in the software interrupt service routine to solve this problem in this paper. In other words, from the single SWI call to the nested SWI call, I improved the software interrupt use all the more flexibly, and I compared and analyzed the strong and weak points of the two passing ways of the parameters. The main differences between these two ways are speed and readability. The stack pointer getting way incurred a lot of overhead although it has a very great readability. But, the stack pointer passing way producted 19% of the effectivity in speed by reduce overhead.

• IEMEK Journal of Embedded Systems and Applications
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• v.12 no.3
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• pp.159-167
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• 2017

Software safety is a key issue in embedded system of automotive and aviation industries. Various software testing approaches have been proposed to achieve software safety like ISO26262 Part 6 in automotive environment. In spite of one of the classic and basic approaches, stack memory is hard to estimating exactly because of uncertainty of target code generated by compiler and complex nested interrupt. In this paper, we propose an approach of analyzing the maximum stack usage statically from target binary code rather than the source code that also allows nested interrupts for determining the exact stack memory size. In our approach, determining maximum stack usage is divided into three steps: data extraction from ELF file, construction of call graph, and consideration of nested interrupt configurations for determining required stack size from the ISR (Interrupt Service Routine). Experimental results of the estimation of the maximum stack usage shows proposed approach is helpful for optimizing stack memory size and checking the stability of the program in the embedded system that especially supports nested interrupts.