Hi ,
i require help to access the PC27/CP26/PC25/PC24 GPIO pins, present in the SV1 header.

I am able to access the inbuild LEDs using program given by the vendor. Those LEDs are connected in PC18, PC19,PC20. I have used the same method, but not able access the external GPIOs.

the code is below,

if ((memMapFile = open("/dev/mem", O_RDWR | O_SYNC)) < 0)
{
printf("ERROR: Unable to open /dev/mem\n");
return (DRIVER_NOT_FOUND);
}

at91SysCtrlr = mmap(NULL, 4096, PROT_READ | PROT_WRITE,
MAP_SHARED, memMapFile, (unsigned)AT91C_BASE_SYS);

if (at91SysCtrlr == MAP_FAILED)
{
printf("ERROR: Unable to mmap the system controller\n");
close (memMapFile);
memMapFile = -1;
return (MEMMAP_FAILED);
}

/* set LED signals for output */
/* set digital output ports init value = all on (active low) */
at91SysCtrlr->PIOC_CODR = GPIO_LED_MASK;
at91SysCtrlr->PIOC_PPUDR = GPIO_LED_MASK;
at91SysCtrlr->PIOC_PER = GPIO_LED_MASK;
at91SysCtrlr->PIOC_OER = GPIO_LED_MASK;


if ((memMapFile = open("/dev/mem", O_RDWR | O_SYNC)) < 0)
{
printf("ERROR: Unable to open /dev/mem\n");
return (DRIVER_NOT_FOUND);
}

at91SysCtrlr = mmap(NULL, 4096, PROT_READ | PROT_WRITE,
MAP_SHARED, memMapFile, (unsigned)AT91C_BASE_SYS);

if (at91SysCtrlr == MAP_FAILED)
{
printf("ERROR: Unable to mmap the system controller\n");
close (memMapFile);
memMapFile = -1;
return (MEMMAP_FAILED);
}

/* set LED signals for output */
/* set digital output ports init value = all on (active low) */
at91SysCtrlr->PIOC_CODR = GPIO_LED_MASK;
at91SysCtrlr->PIOC_PPUDR = GPIO_LED_MASK;
at91SysCtrlr->PIOC_PER = GPIO_LED_MASK;
at91SysCtrlr->PIOC_OER = GPIO_LED_MASK;
}

at91SysCtrlr->PIOC_CODR=(ledSignalMapping[ledindex]);

inbuild LEDs are glowing, but the LEDs connected in the external GPIO pins are not glowing.
any help appriciated.
thanks
suresh