报这个错误什么原因？

luofeng

//DB0~DB15

#define DATAOUT(x){\

GPIOB->ODR&=0XFF00;\

GPIOB->ODR&=(x);\

GPIOC->ODR&=0X00FF;\

GPIOC->ODR&=(x);};

#define DATAIN     (GPIOC->IDR&0X00FF)&(GPIOB->IDR&0XFF00);

void LCD_WR_DATA(u16 data)

{

LCD_RS_SET;

LCD_CS_CLR;

DATAOUT(data);

LCD_WR_CLR;

LCD_WR_SET;

LCD_CS_SET;

}

..\hardware\lcd.c(28): error:  #137: expression must be a modifiable lvalue

..\hardware\lcd.c(28): error:  #137: expression must be a modifiable lvalue

..\hardware\lcd.c(28): error:  #137: expression must be a modifiable lvalue

..\hardware\lcd.c(28): error:  #137: expression must be a modifiable lvalue

aleda303

\ 后面是不是有空格