If i2c tools are not working your script won't work either.

Your really need to show more info to troubleshoot this...

Chip address conflict perhaps?
On Dec 11, 2014 12:39 AM, <[email protected]> wrote:

>
>
> On Thursday, December 11, 2014 11:39:35 AM UTC+5:30, [email protected]
> wrote:
>>
>> Hi,
>>
>> I am trying to read two bytes of data from a board(slave) using
>> BBB(master) through i2c interface.
>>
>> I connected my board's SDA and SCL lines to P9_18 and P9_17 of BBB
>> respectively.
>>
>> My code is
>>
>> #include <stdio.h>
>> #include <errno.h>
>> #include <string.h>
>> #include <fcntl.h>
>> #include <stdlib.h>
>> #include <unistd.h>
>> #include <linux/i2c-dev.h>
>> #include <sys/ioctl.h>
>>
>>
>> int main()
>> {
>> int fd,i;
>>     int addr = 0x43;
>> char buffer[10] = {0};
>>
>> fd = open("/dev/i2c-1", O_RDWR);   // opening i2c-1 file. returns a file
>> descriptor used by read
>> if(fd < 0)
>> {
>> printf("i2c failed to open\n");
>> }
>>
>> if(ioctl(fd, I2C_SLAVE, addr) < 0)
>> printf("failed to acquire bus\n");
>>
>> if(read(fd,buffer,2) != 2)     //reading 2 bytes of data
>> {
>> printf("i2c read failed\n");
>>
>> }
>> else
>> {
>> for(i=0;i<2;i++)
>> printf("the data is %d \n",buffer[i]);
>> }
>>
>>
>> return 0;
>> }
>>
>>
>>
>>
>>
>>
>> I got output --- "i2c read failed"
>>
>> What is the problem in my code? Or any problem in hardware? When I
>> checked the following command, I got output like
>>
>> root@beaglebone:~# i2cdetect -l
>> i2c-0   i2c             OMAP I2C adapter                        I2C
>> adapter
>> i2c-1   i2c             OMAP I2C adapter                        I2C
>> adapter
>> root@beaglebone:~# ls -l /sys/bus/i2c/devices/i2c-*
>> lrwxrwxrwx 1 root root 0 Jan  1  2000 /sys/bus/i2c/devices/i2c-0 ->
>> ../../../devices/ocp.3/44e0b000.i2c/i2c-0
>> lrwxrwxrwx 1 root root 0 Jan  1  2000 /sys/bus/i2c/devices/i2c-1 ->
>> ../../../devices/ocp.3/4819c000.i2c/i2c-1
>>
>>
>> Can anyone find problem? Please reply.
>>
>
>
> I tried i2cget command but it also showing Error: Read failed.
>
> What it means? Any hardware problem? How i trace the problem?
>
>
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>
> --
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