【经验分享】KL25官方第10版sample code中BME代码补丁

1万 · 2014-1-24 16:19

本帖最后由 FSL_TICS_ZJJ 于 2014-10-21 14:41 编辑

大家如果在调试KL25第10版sample code代码的BME工程时，发现打印出的结果显示BME代码确没有普通C代码跑的快，请不要惊慌，本文教您如何解决！

由于第10版SC中BME.h 头文件写的比较冗余，不利于体现BME的优势，先将头文件做如下改写：
这里以BME_AND_W 函数为例。
原描写方式为：

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_BME_INLINE void BME_AND_W (volatile uint32_t *addr, register uint32_t wdata)



{ 



*(volatile uint32_t*)((uint32_t)addr | BME_AND_MASK) = wdata;



}

现在修改为宏定义的方式：

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#define BME_AND_W(addr, wdata) \



*(volatile uint32_t*)((uint32_t)addr | BME_AND_MASK) = wdata;

最终的打印结果显示为：

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Running the LQRUG_bme_ex1 project.







systick start value: 0xFFFFF2







systick end value: 0xFFFFEE







systick current value read overhead: 0x4







systick start value: 0xFFFFD6







systick end value: 0xFFFFC2







actual execution cycle for logic operation with normal C code: 0x10







systick start value: 0xFFFFD7







systick end value: 0xFFFFC9







actual execution cycle for logic operation with BME macros: 0xA







systick start value: 0xFFFFE7







systick end value: 0xFFFFD3







actual execution cycle for BFI operation with normal C: 0x10







systick start value: 0xFFFFEE







systick end value: 0xFFFFE0







actual execution cycle for BFI operation with BME macro: 0xA







load_bit is 1







systick start value: 0xFFFFDF







systick end value: 0xFFFFCB







actual execution cycle for LAC1 operation with normal C: 0x10







load bit is 1







systick start value: 0xFFFFE4







systick end value: 0xFFFFD6







actual execution cycle for LAC1 operation with BME macro: 0xA







load_bit is 0







systick start value: 0xFFFFEA







systick end value: 0xFFFFD7







actual execution cycle for LAS1 operation with normal C: 0xF







load bit is 0







systick start value: 0xFFFFE3







systick end value: 0xFFFFD4







actual execution cycle for LAS1 operation with bme macro: 0xB







extracted data is 2







systick start value: 0xFFFFE9







systick end value: 0xFFFFD8







actual execution cycle for UBFX operation with normal C: 0xD







extracted data is 2







systick start value: 0xFFFFEF







systick end value: 0xFFFFE2







actual execution cycle for UBFX operation with bme macro: 0x9