Keil board MCBSTR9
 

erm... anyone know what is this declaration mean?

#define LCD_DATA GPIO8->DR[0xFF<<2]     /* Data bits D0 = P8.0 .. DB7 = P8.7  */

#define LCD_E    GPIO9->DR[0x01<<2]     /* Enable control                     */

#define LCD_RW   GPIO9->DR[0x02<<2]     /* Read/Write control                 */

#define LCD_RS   GPIO9->DR[0x04<<2]     /* Data/Instruction control           */

#define LCD_CTRL GPIO9->DR[0x07<<2]     /* All 3 control lines (E/RW/RS)      */



#define E_ENA    0x01

#define E_DIS    0x00

#define RW_READ  0x02

#define RW_WRITE 0x00

#define RS_DATA  0x04

#define RS_INST  0x00