No data on bus using mmap on ARM9 board

Hi, there

I am using mmap on S3C2410 ARM9 board to write the data to SRAM, I can get nGCS2 and WE pulse, but there is no data on data bus, the code is listed below.

What could be the problem?

Thanks in advance.

int TestBus() { /*write data to an ADDR */ unsigned char chKey; unsigned int *pBuf = NULL; int mem_fd = 0;

unsigned int GPEDATA = 0; unsigned int gpio_mem = 0;

printf("Bus Test\n");

mem_fd = open("/dev/mem", O_RDWR);

if ( 0 == mem_fd) { perror("open"); return -1; }

gpio_mem = (unsigned long int) mmap(NULL, 0x10000, PROT_READ | PROT_WRITE, MAP_SHARED, mem_fd, 0x10000000);

if (-1 == gpio_mem) { perror("mmap"); close(mem_fd); return -1; }

pBuf = (unsigned int *)gpio_mem;

printf("Write 0xf0f0 to Bus Press q to exit");

pBuf[0] = 0xffffff;

while (1) { scanf("%c", &chKey);

if ('q' == chKey) { break; } pBuf[0] = 0xf0f0; }

close(mem_fd);

return 0; }