知识点：按键（控制变量改变）+LCD

定义变量

uint8_t key_val,key_up,key_down,key_old;
uint16_t X=2,Y=2,T;
char buf[21];

函数声明 

uint8_t key_scan(void);
void key_proc(void);
void lcd_Proc(void);

 按键

//按键扫描
uint8_t key_scan(void)
{
key_val=0;
if(HAL_GPIO_ReadPin(GPIOB,GPIO_PIN_1)==GPIO_PIN_RESET)
{
key_val=2;
}
if(HAL_GPIO_ReadPin(GPIOB,GPIO_PIN_2)==GPIO_PIN_RESET)
{
key_val=3;
}
return key_val;
}//按键执行
void key_proc(void)
{
key_val=key_scan();
key_down=key_val&(key_val^key_old);
key_up=~key_val&(key_val^key_old);	
key_old=key_val;
if(key_down==2)
{
X++;
if(X==51)
{X=1;
}
}
if(key_down==3)
{Y++;
if(Y==21)
{
Y=1;
}
}
}

 显示

void lcd_Proc(void)
{T=X*Y;
LCD_DisplayStringLine(Line2,(uint8_t*)"        DATA       ");
sprintf(buf,"        X:%d        ",X);
LCD_DisplayStringLine(Line3,(uint8_t*)buf);
sprintf(buf,"        Y:%d        ",Y);
LCD_DisplayStringLine(Line4,(uint8_t*)buf);
sprintf(buf,"        T:%d        ",T);
LCD_DisplayStringLine(Line5,(uint8_t*)buf);}