According to the strict requirement on software real-time in critical areas like aerospace,military and nuclear industry,it introduces a code execution time measurement method based on μC/OS-Ⅱ real-time operating system.The paper analyzes factors which affect time measurement most,and get rid of them at last.Using SoftConsole IDE,it implements related code on control chip SmartFusion which is based on Cortex-M3.It measures some real-time indexes of μC/OS-Ⅱ on SmartFusion platform,which gives a time referenc...