问         用GCC编译的AMEG8中的休眠指令是什么?我用SLEEP为什么不能通过? 答 1: 看gcc的手册5.5 Power Management and Sleep Modes
5.5.1 Detailed Description
#include <AVR/sleep.h>
Use of the SLEEP instruction CAN allow your application to reduce it’s power com-sumption
considerably. AVR devices CAN be put into different sleep modes by chang-ing
the SMn bits of the MCU Control Register ( MCUCR ). Refer to the datasheet for the
details relating to the device you are using.
Sleep Modes
Note:
Some of these modes are not available on all devices. See the datasheet for target
device for the available sleep modes.
&#8226; #define SLEEP MODE IDLE 0
&#8226; #define SLEEP MODE ADC BV(SM0)
&#8226; #define SLEEP MODE PWR DOWN BV(SM1)
&#8226; #define SLEEP MODE PWR SAVE ( BV(SM0) | BV(SM1))
&#8226; #define SLEEP MODE STANDBY ( BV(SM1) | BV(SM2))
&#8226; #define SLEEP MODE EXT STANDBY ( BV(SM0) | BV(SM1) | BV(SM2))
Sleep Functions
&#8226; void set sleep mode (uint8 t mode)
&#8226; void sleep mode (void)
答 2: 是啊，要用setsleepmode()和sleepmode()才行或者这样也可以：
  asm volatile("sleep"::);
注意这之前要先设置睡眠模式。

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