gpio.zip_gpio 2440

#define GPFCON (*(volatile unsigned long *)0x56000050) #define GPFDAT (*(volatile unsigned long *)0x56000054) #define GPGCON (*(volatile unsigned long *)0x56000060) #define GPGDAT (*(volatile unsigned long *)0x56000064) /* * LED1,LED2,LED4对应GPF4、GPF5、GPF6 */ #define GPF4_out (1<<(4*2)) #define GPF5_out (1<<(5*2)) #define GPF6_out (1<<(6*2)) #define GPF4_msk (3<<(4*2)) #define GPF5_msk (3<<(5*2)) #define GPF6_msk (3<<(6*2)) /* * S2,S3,S4对应GPF0、GPF2、GPG3 */ #define GPF0_in (0<<(0*2)) #define GPF2_in (0<<(2*2)) #define GPG3_in (0<<(3*2)) #define GPF0_msk (3<<(0*2)) #define GPF2_msk (3<<(2*2)) #define GPG3_msk (3<<(3*2)) int main() { unsigned long dwDat; // LED1,LED2,LED4对应的3根引脚设为输出 GPFCON &= ~(GPF4_msk | GPF5_msk | GPF6_msk); GPFCON |= GPF4_out | GPF5_out | GPF6_out; // S2,S3对应的2根引脚设为输入 GPFCON &= ~(GPF0_msk | GPF2_msk); GPFCON |= GPF0_in | GPF2_in; // S4对应的引脚设为输入 GPGCON &= ~GPG3_msk; GPGCON |= GPG3_in; while(1){ //若Kn为0(表示按下)，则令LEDn为0(表示点亮) dwDat = GPFDAT; // 读取GPF管脚电平状态 if (dwDat & (1<<0)) // S2没有按下 GPFDAT |= (1<<4); // LED1熄灭 else GPFDAT &= ~(1<<4); // LED1点亮 if (dwDat & (1<<2)) // S3没有按下 GPFDAT |= (1<<5); // LED2熄灭 else GPFDAT &= ~(1<<5); // LED2点亮 dwDat = GPGDAT; // 读取GPG管脚电平状态 if (dwDat & (1<<3)) // S4没有按下 GPFDAT |= (1<<6); // LED3熄灭 else GPFDAT &= ~(1<<6); // LED3点亮 } return 0; }