Proceedings of International Conference on Applied Innovation in IT
2014/03/27, Volume 2, Issue 1, pp.7-9
System Time Issues for the ARM Cortex A8 Processor
Irina Fedotova, Eduard Siemens
Abstract: The use of system-on-chip (SoC) platforms has emerged as an important integrated circuit design trend for communication and industrial control applications. At the same time, requirements of stable, efficient and precise processing time values are growing rapidly. Since the ARM processor doesn't possess known timers of PC-platforms such as TSC counter or HPET timer, the common way to obtain time values on ARM-architecture is still only through Linux system calls which are mapped to ARM specific time counters. Indeed, direct access to hardware can help to reduce costs down to 200 nanoseconds against 2-1 microseconds of the time acquisition via Unix system call interface. However, designing this approach is a challenging task. This paper describes specific issues and features of tracking system time on the ARM Cortex A8 processor under Linux OS.
Keywords: timestamp precision, time-keeping, embedded Linux, ARM architecture
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