首先,端口的八个GPIO共用一个中断向量.
每个GPIO能够独立配置上升下降作为中断触发条件.
但是这个功能实际上没有太大用处,因为STM8的GPIO中断居然只有中断使能位,没有中断标志位!
举例说明:
想要在A1,A2口上实现两个必须上升沿触发中断的按钮或者外设,需要共用EXT_A的中断向量.
假设有一时间发生了EXT_A中断,进入了中断服务函数.现在没有中断标志位,直接导致要用很复杂的算法才能判断到底是哪个口上发生的中断.
友情提示: 此问题已得到解决，问题已经关闭,关闭后问题禁止继续编辑，回答。
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你要求他能代替Intel i7这是你的不对...
EXTI, unlike other interrupts, does not have its own status register / flag, as you indicated.
However, you can easily use a static variable to remember the previous state of the port and to determine which pins trigger the interrupt.
something like:
- static unsigned char sPORTA=0; //porta shadow register
-
- tmp = PORTA ^ sPORTA; //which pins have changed -> pins that have changed will be 1
- //alternatively to detect a falling edge
- //tmp = (PORTA ^ sPORTA) & sPORTA; //which pins have a falling edge
- sPORTA = PORTA; //save portA's current reading
- ...
复制代码you can further AND tmp with Px_CR2 register to just read the ones that you have activated for EXTI.Unusual but not too complicated
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