Question

51单片机如何将常量定义在flash中，例如点阵的编码等，因为51的ram太小了！

Answer 1

在变量声明前加const关键字即可。

Answer 2

extern unsigned char code shezhi7_1[]={"开关机 [ ]\0"};
extern unsigned char code shezhi7_2[]={"0:开机 1:关机\0"};
extern unsigned char code shezhi7_3[]={"ONOFF [ ]\0"};
extern unsigned char code shezhi7_4[]={"0:ON 1:OFF\0"};
extern unsigned char code shezhi9_1[]={"主动孤岛允许 [ ]\0"};
extern unsigned char code shezhi9_2[]={"0:禁止 1:允许\0"};
明白了吗？ 用关键字code

Answer 3

加code 例如 unsigned char code st[];