Re: [ts-7000] PLD registers, still not getting access to memory regs

["Don W. Carr" <>]

You proplem is this line:

if ((int)pld_regs=-1) {

should be:

if ((int)pld_regs == -1) {

Your line asignes -1 to pld regs (overwriting the pointer you recieved), then, anything non-zero is true in C.

But, better yet, and more readable:

if ((MAP_FAILED == pld_regs) {

Never do dangerous casts that you might not understand if you do not have to. Also, put the constant always on the left, that way if you put = instead of ==, the compiler will complain about asigning to a constant. Take the time to write good, readable code. You will spend less time in the long run and end up with a more reliable product.

Hope this helps.

Don.

On 9/1/06, mattsaintdev <> wrote:

Hi,
posted a similar request a few weeks ago but after help still not
getting a handle to the PLD registers of the video card.

Once problem was that i needed to be SU to do an open on "dev/mem"
but still the pointer to "pld_regs=(unsigned char *)mmap(" is
returning a -1. Checked page size btw which is 4096.

I dont have a problem mapping the video buffer though?

Code below, any suggestions?

Thanks

Matt

#include <unistd.h>
#include <sys/types.h>
#include <sys/mman.h>
#include <stdio.h>
#include <stdlib.h>
#include <fcntl.h>

volatile unsigned char *pld_regs;

int main(int argc, char **argv)
{

char base7;
int mem_handle=open("/dev/mem", O_RDWR | O_SYNC);
//
// 0x11E0_0000 = PLD Register base address

printf("mem handle = %d\n", mem_handle);

pld_regs=(unsigned char *)mmap(0, 4096 , PROT_READ|PROT_WRITE,
MAP_SHARED, mem_handle, 0x11E00000);

if ((int)pld_regs=-1) {
printf("MMap failed.\n Page size = %d\n",getpagesize() );
exit(1);
}
//
//
//
//
printf("TS-7KV Register settings probe \n");
printf("------------------------------ \n\n");
printf("BASE+0 Board ID #1 = %X (documented as 0x41)\n", pld_regs
[0xE0] );
printf("BASE+1 Board ID #2 = %X (documented as 0x20)\n", pld_regs
[0xE1] );

base7=pld_regs[0xE7];
if (base7 & 0x80) printf("ADC option is installed\n");
if (base7 & 0x40) printf("CAN option is installed\n");
if (base7 & 0x20) printf("J5 Set\n");
if (base7 & 0x10) printf("J4 Set\n");
if (base7 & 0x08) printf("J3 Set\n");
if (base7 & 0x04) printf("J2 Set\n");
if (base7 & 0x02) printf("J1 Set\n");
//
//
return 0;
}

-- 
Dr. Don W. Carr
J. G. Montenegro 2258
Guadalajara, Mexico
+52-333-630-0704
+52-333-836-4500 ext 2930

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