/* Example how to access the value of the on-board DIP switches on* HiCO.SH7760. You can compile the program with command:** sh4-linux-gcc -Wall dip_switch.c -o dip_switch*/
#include <stdio.h>
#include <stdlib.h>
#include <assert.h>
#include <unistd.h>
#include <errno.h>
#include <fcntl.h>
#include <sys/mman.h>#define MAP_SIZE 4096UL
#define MAP_MASK (MAP_SIZE - 1)int main(void) {int fd;void *map_base, *virt_addr;/* Physical address of the DIP switch GPIO register on HiCO.SH7760 (See* the HiCO.SH7760 hardware manual ** _NOTE_: the dipswitches also define how the system boots (i.e. the value* is used by the bootloader at startup), so oafter testting, leave the* switches in the same position as they were */off_t target = 0x7F008800; //GPKCON0 0x7F008800 if((fd = open("/dev/mem", O_RDWR | O_SYNC)) == -1) {printf("/dev/mem could not be opened.\n");perror("open");exit(1);} else {printf("/dev/mem opened.\n");}/* Map one page */map_base = mmap(0, MAP_SIZE, PROT_READ | PROT_WRITE, MAP_SHARED, fd, target & ~MAP_MASK);if(map_base == (void *) -1) {printf("Memory map failed.\n");perror("mmap");} else {printf("Memory mapped at address %p.\n", map_base);}virt_addr = map_base + (target & MAP_MASK);/* acess remapped region here */printf("Now try to change the value of the on-board DIP switche\n");*(unsigned int *)virt_addr=0x11110000;//0x1111<<16;//設定為輸出狀態int ab=*(unsigned int *)virt_addr;//*(unsigned int *)(virt_addr+8)=0xffffffff;printf("ab=%x\n",ab);#if 1while(1){*(volatile unsigned int *)(virt_addr+8)=0x00; //一定要是virt_addr不能是map_base//置０亮printf("1value is 0x%x\n",*(unsigned int *)(virt_addr+8));printf("2value is 0x%x\n",*(unsigned int *)virt_addr);sleep(1); //一定要有要不很快，人眼發現不了*(volatile unsigned int *)(virt_addr+8)=0xf0; //置１滅printf("3value is 0x%x\n",*(unsigned int *)(virt_addr+8));printf("4value is 0x%x\n",*(unsigned int *)virt_addr);sleep(1); //一定要有要不很快，人眼發現不了}#endif/* we'll never get here in this example, but here's how the region is* unmapped. */if(munmap(map_base, MAP_SIZE) == -1) {printf("Memory unmap failed.\n"); }close(fd);
}
