AVR笔记2：界说F_CPU

1.warning:#warning“F_CPUnotdefinedfor“

2.warning: “F_CPU” redefined

3.c:/winavr-20100110/lib/gcc/../../avr/include/util/delay.h:86:1: warning: this is the location of the previous definition

呈现以上三种过错的解决办法是将#define F_CPU 1000000

放在在#include句子之前，如下：

#define F_CPU 1000000
#include
#include