第一个：
#include <sys/mman.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <stdio.h>
#define LED_PHY_BASE 0x56000050
int main(void)
{
int fd = -1;
volatile unsigned int *pAddr = NULL;
fd = open("/dev/mem",O_RDWR);
if(fd < 0) {
printf("Can't open the /dev/mem device!\n");
}
pAddr = mmap(0, getpagesize(), PROT_READ|PROT_WRITE, MAP_SHARED,fd, LED_PHY_BASE);
*pAddr = ~0xff00;
*pAddr |= 0x5500;
*(pAddr +8) = 0xf0; //diable pull-up funaction
while(1) {
*(pAddr+4) = 0x70; //Lighten D9
sleep(1);
*(pAddr +4)= 0xf0;
sleep(1);
}
return 0;
}
第二个：
#include <sys/mman.h>
#include <unistd.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <fcntl.h>
#include <stdio.h>
#define GPIO_BASE 0x56000000
#define GPFCONF_OFFSET 0x50
#define GPFDAT_OFFSET 0x54
#define GPFUP_OFFSET 0x58
volatile unsigned int *GPFCONF;
volatile unsigned int *GPFDAT;
volatile unsigned int *GPFUP;
int main(void)
{
int fd = -1;
unsigned char *pAddr = NULL;
fd = open("/dev/mem",O_RDWR|O_SYNC);
if(fd < 0) {
printf("Can't open the /dev/mem device!\n");
}
pAddr = (unsigned char *)mmap(0, getpagesize(), PROT_READ|PROT_WRITE, MAP_SHARED,fd, GPIO_BASE);
if (pAddr == MAP_FAILED) {
printf("mmap error!\n");
close(fd);
return -1;
}
GPFCONF = (unsigned int *)(pAddr+GPFCONF_OFFSET);
GPFDAT = (unsigned int *)(pAddr+GPFDAT_OFFSET);
GPFUP = (unsigned int *)(pAddr+GPFUP_OFFSET);
*GPFCONF &= ~0xff00;
*GPFCONF |= 0x5500;
printf("GPFCONF=0x%0x\n", *GPFCONF);
*GPFUP = 0xf0; //diable pull-up funaction
printf("GPFUP=%0x\n", *GPFUP);
while(1) {
*GPFDAT = 0x70; //Lighten D9
printf("GPFDAT=%0x\n", *GPFDAT);
usleep(200000);
*GPFDAT= 0xf0;
printf("GPFDAT=%0x\n", *GPFDAT);
usleep(200000);
}
munmap((void *)pAddr, getpagesize());
return 0;
}
第三个：
#include <stdio.h>
#include <sys/mman.h>
#include <termios.h>
#include <sys/types.h>
#include <sys/stat.h>
#include <unistd.h>
#include <fcntl.h>
#include <string.h>
#define BLOCKSIZE (unsigned long) 1
#define OFFSET_A (unsigned long) 0
#define OFFSET_B (unsigned long) 1
#define OFFSET_C (unsigned long) 2
#define ASCII_a 97
#define ASCII_z 122
int main(int argc, char **argv)
{
int fd_flash, fd_ram;
int index;
struct termios lterm, old_lterm;
char * block0;
char * block1;
char * block2;
int pagesize;
unsigned char data;
tcgetattr(0, <erm);
old_lterm = lterm;
lterm.c_lflag &= ~ICANON;
tcsetattr(0, TCSANOW, <erm);
if (argc != 3) {
printf("usage: mmap_demo <flash_file> <ram_file>\n");
return -1;
}
pagesize = getpagesize();
printf("Pagesize is %d\n", pagesize);
if ((fd_flash = open (argv[1], O_RDWR)) < 0)
perror ("can't open flash file for rd/wr");
if ((fd_ram = open (argv[2], O_RDWR)) < 0)
perror ("can't open ram file for rd/wr");
if ((block0 = mmap (0, BLOCKSIZE*pagesize, PROT_WRITE|PROT_READ, MAP_SHARED, fd_flash, OFFSET_A * pagesize ))
== (caddr_t) -1)
perror ("mmap error for block0");
if ((block1 = mmap (0, BLOCKSIZE*pagesize, PROT_WRITE|PROT_READ, MAP_PRIVATE, fd_flash, OFFSET_B * pagesize ))
== (caddr_t) -1)
perror ("mmap error for block1");
if ((block2 = mmap (0, BLOCKSIZE*pagesize, PROT_WRITE|PROT_READ, MAP_SHARED, fd_ram, OFFSET_C * pagesize ))
== (caddr_t) -1)
perror ("mmap error for block2");
index = 0;
data = ASCII_a;
while ( 1 ) {
printf("%4X: %2X %2X %2X\n cmd: ", index, *(char *)(block0+index), *(char *)(block1+index), *(char *)(block2+index) );
int c = getchar();
printf("\n");
switch (c) {
case '+':
index++;
if (index>(BLOCKSIZE*pagesize-1)) index=(BLOCKSIZE*pagesize-1);
printf("index = %4X\n", index);
break;
case '-':
index--;
if (index<0) index=0;
printf("index = %4X\n", index);
break;
case 'u':
index+=0x100;
if (index>(BLOCKSIZE*pagesize-1)) index=(BLOCKSIZE*pagesize-1);
printf("index = %4X\n", index);
break;
case 'd':
index-=0x100;
if (index<0) index=0;
printf("index = %4X\n", index);
break;
case 'r':
data=ASCII_a;
break;
case 'w':
printf("write %2X: ", data);
if (memcpy(block0+index, (void *)&data, sizeof(unsigned char)) != block0+index) {
printf("F "); } else { printf("P "); }
if (memcpy(block1+index, (void *)&data, sizeof(unsigned char)) != block1+index) {
printf("F "); } else { printf("P "); }
if (memcpy(block2+index, (void *)&data, sizeof(unsigned char)) != block2+index) {
printf("F "); } else { printf("P "); }
printf("\n");
data++;
if (data>ASCII_z) data=ASCII_a;
break;
case 'c':
printf("Copying block2 to block1\n");
if (munmap (block1, BLOCKSIZE != 0))
perror ("munmap error for block1");
if ((block1 = mmap (0, BLOCKSIZE, PROT_WRITE|PROT_READ, MAP_SHARED, fd_flash, OFFSET_B * pagesize ))
== (caddr_t) -1)
perror ("mmap error for block1");
if (memcpy(block1, block2, BLOCKSIZE*pagesize) != block1)
perror("Error copying data over to block1\n");
if (munmap (block1, BLOCKSIZE != 0))
perror ("munmap error for block1");
if ((block1 = mmap (0, BLOCKSIZE, PROT_WRITE|PROT_READ, MAP_PRIVATE, fd_flash, OFFSET_B * pagesize ))
== (caddr_t) -1)
perror ("mmap error for block1");
break;
case 'q':
goto all_done;
break;
case 's':
printf("sync'ing writes\n");
if (msync(block0, BLOCKSIZE, MS_SYNC) != 0)
perror ("error msync of block0");
break;
}
}
all_done:
if (munmap (block0, BLOCKSIZE != 0))
perror ("munmap error for block0");
if (munmap (block1, BLOCKSIZE != 0))
perror ("munmap error for block1");
if (munmap (block2, BLOCKSIZE != 0))
perror ("munmap error for block2");
if (close(fd_flash) != 0)
perror ("error closing fd_flash");
if (close(fd_ram) != 0)
perror ("error closing fd_ram");
tcsetattr(0, TCSANOW, &old_lterm);
printf("\n");
return 0;
}
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