大家好~
现在在看TI 的带HALL的BLDC电机控制例程，其中有个函数不太理解，请高人帮忙给解毒一下！
文件：f2803xhall_gpio.h
函数：#define HALL3_DEBOUNCE_MACRO(v)
问题：
1 这个函数是去抖动原理是什么，代码如何实现的！
2 v.EdgeDebounced 结构体变量是做什么用的？
谈谈个人的理解，可能与TI给出的例程解释有出入。
首先当进入去抖程序后，先判断v.HallGpio是否有变化（v.HallGpio == v.HallGpioAccepted）
1）如果没变化，就不存在去抖动问题，所以不太理解下面的代码在做什么？
v.StallCount -= 1; /* Decrement stall counter*/ \
if (v.StallCount == 0) \
{ \
v.EdgeDebounced = 0x7FFF; /* 0x7FFF If motor has stalled, then user trigger to commutate*/\
v.StallCount = 0xFFFF; /* Reset counter to starting value*/ \
} \
\
v.DebounceCount = 0;
2）假设v.HallGpio有变化，这时候需要判断是不是抖动造成的（去抖），“ if (v.DebounceCount >= v.DebounceAmount)”这个语句才应该是真正的去抖动，
通过DebounceAmount设置一个去抖动滤波的时间和v.DebounceCount += 1操作，把v.HallGpioAccepted = v.HallGpioBuffer，形成确定的hall状态。
完整代码如下：
if (v.HallGpio == v.HallGpioAccepted) /* GPIO_UNCHANGED: Current GPIO reading == debounced ..*/ \
/*..GPIO reading, no change in state (no edge yet) */ \
{ \
if (v.Revolutions <= 0) /* Only create hall map during initial Revolutions*/ \
HALL3_CREATE_MAP(v) \
\
v.StallCount -= 1; /* Decrement stall counter*/ \
if (v.StallCount == 0) \
{ \
v.EdgeDebounced = 0x7FFF; /* 0x7FFF If motor has stalled, then user trigger to commutate*/\
v.StallCount = 0xFFFF; /* Reset counter to starting value*/ \
} \
\
v.DebounceCount = 0; \
} \
else /* GPIO_CHANGED: Motor might have moved to a new position.*/ \
{ \
if (v.HallGpio == v.HallGpioBuffer) /* Current GPIO reading == previous GPIO reading?*/ \
{ \
if (v.DebounceCount >= v.DebounceAmount) /* If equal, is current GPIO reading debounced?*/ \
{ \
v.HallGpioAccepted = v.HallGpioBuffer; /* Current GPIO reading is now debounced*/ \
v.EdgeDebounced = 0x7FFF; /*Edge/position debounced, trigger commutation*/\
\
v.StallCount = 0xFFFF; /* On new edge, reset stall counter*/ \
v.CapCounter += 1; /* Increment running edge detection counter*/ \
\
v.DebounceCount = 0; /* Reset debounce counter*/ \
\
if (v.HallMapPointer==0) \
v.Revolutions += 1; /* Increment on every rev (HallMapPointer = 0)*/ \
} \
else /* DEBOUNCE_MORE*/ \
v.DebounceCount += 1; /* Increment debounce counter*/ \
} \
else /* NEW_READING*/ \
{ \
v.HallGpioBuffer = v.HallGpio; /* Save new reading and reset debounce counter*/ \
v.DebounceCount = 0; \
} \
}
