求助：MC9S12P如何配置进入Wait 或 Stop Mode

jen-385781

周期性唤醒有没有做过实验？

jen-385781

周期性唤醒有没有做过实验？

至简致远

回复第 9 楼 于2012-11-26 14:39:33发表:
用非屏蔽中断唤醒。问下，唤醒程序是什么流程 

执行DisableInterrupts；之后 ， 非屏蔽中断也不能使用了……

jen-385781

Upon exit of wait and pseudo-stop, the CPU fetches the interrupt vector
associated with the wake-up event. Note that this does not apply to wake-up
from XIRQ when X mask bit is set. In this case (XIRQ interrupt disabled),
execution continues with the next instruction after STOP. The application
re-starts almost immediately given that the oscillator is still running.
Upon exit from stop mode, the same process applies. However, there will be
an additional delay caused by the oscillator start-up. This delay varies greatly
depending on the oscillator configuration (Colpitts or Pierce) and whether the
application uses a crystal or a resonator as clock reference. Please refer to the
Clock and Reset Generation (CRG) Block User Guide for more information about the oscillator. Timings are similar to the oscillator start-up at power-up of
the microcontroller. The fastest oscillator start-up is obtained by using a
resonator in the Pierce oscillator configuration.

jen-385781

Upon exit of wait and pseudo-stop, the CPU fetches the interrupt vector
associated with the wake-up event. Note that this does not apply to wake-up
from XIRQ when X mask bit is set. In this case (XIRQ interrupt disabled),
execution continues with the next instruction after STOP. The application
re-starts almost immediately given that the oscillator is still running.
Upon exit from stop mode, the same process applies. However, there will be
an additional delay caused by the oscillator start-up. This delay varies greatly
depending on the oscillator configuration (Colpitts or Pierce) and whether the
application uses a crystal or a resonator as clock reference. Please refer to the
Clock and Reset Generation (CRG) Block User Guide for more information about the oscillator. Timings are similar to the oscillator start-up at power-up of
the microcontroller. The fastest oscillator start-up is obtained by using a
resonator in the Pierce oscillator configuration.

至简致远

回复第 10 楼 于2012-11-26 14:48:20发表:
可以不用关闭中断访问，但是要针对各个模块要关闭中断。需要唤醒功能的模块中断开启，就可以了。还有，要注意定时器中断，时间太短的话，也会发生问题。比如1ms中断，在我们看来，没有进入STOP模式，其实已经进去了，只是中断发生频繁，而导致程序会运行。 

Thank you very much!   后续有问题有可能还要打扰哦！！！

jen-385781

回复第 10 楼 于2012-11-26 14:48:20发表:
可以不用关闭中断访问，但是要针对各个模块要关闭中断。需要唤醒功能的模块中断开启，就可以了。还有，要注意定时器中断，时间太短的话，也会发生问题。比如1ms中断，在我们看来，没有进入STOP模式，其实已经进去了，只是中断发生频繁，而导致程序会运行。 

请教下版主，stop mode 下，可以用API周期性唤醒吗？

小成说事

可以用RTI、外部中断唤醒，也可以试用串口，CAN等模块唤醒。

至简致远

回复第 18 楼 于2012-11-26 16:47:22发表:
可以用RTI、外部中断唤醒，也可以试用串口，CAN等模块唤醒。 

你好， 在进入Wait mode 后 看门狗继续工作，会使系统复位，为避免此情况，打算在进入Wait Mode 之前禁止看门狗，唤醒之后再使能看门狗。    但是看门狗在初始化开启之后能禁止吗？  我调试一上午没有做到，  请指教！！   MCU是MC9S12P128

小成说事

看门狗只有在复位的时候才能关闭。或者进入STOP模式自动关闭。