Yeah, I saw those posts of yours :-) Okk, So till you post your blog, I will do the following,
1. Read your last 5 posts 2. try updating my Debian 3. implement your customization 4. read the ADC page that you have sent!! Thanks :-) btw can you suggest me a book or and link where I can learn kind of coding you r doing, embedded coding I guess!! The basics and other stuff!! Once again thanks a lot!! :-) Rathin On Wednesday, September 30, 2015 at 11:36:09 AM UTC+5:30, William Hermans wrote: > > I pretty much followed this guide for ADC setup > http://processors.wiki.ti.com/index.php/Linux_Core_ADC_User's_Guide#Usage > > On Tue, Sep 29, 2015 at 11:03 PM, William Hermans <[email protected] > <javascript:>> wrote: > >> Well it might be you're running in continuous mode. That much I do not >> know, but it could be difference in kernels ? I could not say. >> >> On Tue, Sep 29, 2015 at 11:00 PM, Rathin Dholakia <[email protected] >> <javascript:>> wrote: >> >>> Hi, >>> >>> I tried running your code and I was successful and unsuccessful both!! >>> :-) >>> >>> Success: I could compile code it compiled and when I put "time ./test" I >>> gave me following output >>> >>> real 0m0.011s >>> user 0m0.000s >>> sys 0m0.008s >>> >>> unsuccessful: it didn't show any readings!! >>> My guess is it has something to do with my kernel preemtion, isn't it? >>> >>> On Wednesday, September 30, 2015 at 11:18:20 AM UTC+5:30, William >>> Hermans wrote: >>>> >>>> Oh, and that is using one shot mode. I did not think to use continuous. >>>> BUt I really wanted to see how slow using open(), read(), and close() >>>> really were. Because I had done a lot of reading on the subject, but never >>>> actually used it( I always used mmap() ). >>>> >>>> On Tue, Sep 29, 2015 at 10:41 PM, William Hermans <[email protected]> >>>> wrote: >>>> >>>>> So, I got bored, and decided to do some "screwing around". But took me >>>>> a while because I had not used, or setup the ADC peripheral before, but . >>>>> . >>>>> . here is some quick and dirty code, using std API stuff - Which breaks >>>>> all >>>>> the rules I spoke of in my second post heh. But still pretty darned fast. >>>>> I'd be happier if I could use mmap() directly on >>>>> /sys/bus/iio/devices/iio:device0/in_voltage0_raw, but either I've been >>>>> trying to use an improper mode of operation. Or mmap() on that file >>>>> location is not supported. So, might be forced to use mmap() on /dev/mem >>>>> . >>>>> ..ug! >>>>> >>>>> #include <unistd.h> >>>>>> #include <sys/stat.h> >>>>>> #include <fcntl.h> >>>>>> #include <stdio.h> >>>>>> #include <errno.h> >>>>>> #include <stdlib.h> >>>>>> >>>>>> void read_adc(int fd) >>>>>> { >>>>>> char adc[5] = {0}; >>>>>> int len = read(fd, adc, sizeof(adc - 1)); >>>>>> adc[len] ='\0'; >>>>>> printf("%s ", adc); >>>>>> } >>>>>> >>>>>> int main() >>>>>> { >>>>>> const char *fname = >>>>>> "/sys/bus/iio/devices/iio:device0/in_voltage0_raw"; >>>>>> int count = 0; >>>>>> >>>>>> while( count++ <= 1000){ >>>>>> int fd = open(fname, O_CREAT | O_RDONLY); >>>>>> if(fd == -1){ >>>>>> printf("error: %s\n", strerror(errno)); >>>>>> exit(1); >>>>>> } >>>>>> >>>>>> if(count % 15 == 0 && count != 0) >>>>>> printf("\n"); >>>>>> >>>>>> read_adc(fd); >>>>>> >>>>>> close(fd); >>>>>> } >>>>>> printf("\n"); >>>>>> >>>>>> return 0; >>>>>> } >>>>>> >>>>> >>>>> Output: >>>>> debian@beaglebone:~$ time ./test >>>>> 4016 4020 4007 4010 4008 4010 4005 4005 4013 4015 4015 4011 4008 4001 >>>>> 4010 4006 4006 4011 4007 4011 4003 4009 4006 4005 3995 3999 4005 4000 >>>>> 3997 >>>>> 4008 4016 4009 3997 4008 4011 4013 4011 4012 4009 4006 3997 4007 4007 >>>>> 3999 >>>>> 4014 4014 4007 4015 4008 4011 4012 4012 4007 4013 4016 4017 4016 4016 >>>>> 4013 >>>>> 4006 4013 4015 4006 4013 4009 4003 4011 4011 4017 4015 4008 4005 3998 >>>>> 4000 >>>>> 4002 4011 4012 4010 4013 4009 4010 4010 4010 4010 4011 4008 4007 4007 >>>>> 4007 >>>>> 4013 3998 4006 4007 4003 3999 4009 4005 4013 4018 4019 4014 4012 4003 >>>>> 4008 >>>>> 4010 4017 3999 4002 4008 4008 4008 4004 4010 4008 3996 4002 4009 4014 >>>>> 4011 >>>>> 4012 4006 4007 4004 4000 4008 4008 4010 4008 4007 4006 4003 4007 4000 >>>>> 4008 >>>>> 4003 4010 4003 4006 4006 3996 4001 4003 4000 4002 3996 4007 4003 4011 >>>>> 4013 >>>>> 4012 4017 4013 4008 4002 4010 4005 4013 4016 4014 4012 4015 4013 4013 >>>>> 4007 >>>>> 4011 4008 4010 4014 4016 4016 4015 4018 4013 4016 4005 3997 4007 3998 >>>>> 4007 >>>>> 4002 4004 4009 4007 4010 4010 4001 4005 4008 4003 4010 4012 4013 4006 >>>>> 3994 >>>>> 4014 4006 4008 4009 4014 4015 4012 4012 4013 4010 4012 4014 4015 4020 >>>>> 4017 >>>>> 4017 4013 4010 4020 4014 4012 4010 4008 3997 4002 4001 4012 4010 4006 >>>>> 4016 >>>>> 4010 4004 4004 4004 4003 4004 4004 3999 4003 4007 4008 4006 4005 4006 >>>>> 4007 >>>>> 4013 4013 4011 4010 4010 4005 3996 4002 4008 4012 4012 4007 4006 4000 >>>>> 3999 >>>>> 4009 4005 4013 4010 4008 4012 4011 4015 4016 4017 4013 4009 4008 4007 >>>>> 4006 >>>>> 4015 4012 4010 4013 4011 4016 4012 4013 4012 4009 4007 3998 3995 3998 >>>>> 4004 >>>>> 4003 4011 4009 4001 3998 4007 4008 4001 4008 4008 4012 4013 4007 3998 >>>>> 3999 >>>>> 4015 4007 3997 4005 4009 4007 4002 4009 4015 4012 4007 4009 4013 4017 >>>>> 4015 >>>>> 4010 4005 4011 4017 4015 4010 4013 4012 4004 4008 4012 4010 4014 4015 >>>>> 4013 >>>>> 4016 4016 4016 4007 4009 4011 4010 4009 4010 4010 4004 4004 4002 4002 >>>>> 4011 >>>>> 4008 4007 4004 4010 4006 4008 4007 4005 4006 4008 4002 4009 4013 4011 >>>>> 4006 >>>>> 4010 4015 4014 4016 4018 4015 4017 4015 4015 4018 4016 4013 4011 4013 >>>>> 4016 >>>>> 4017 3998 4012 4006 4008 4014 4011 4003 4012 4018 4014 4012 4005 3994 >>>>> 4000 >>>>> 4004 4003 4007 4012 4012 4005 4005 4006 4008 4001 3999 4004 4000 4004 >>>>> 4000 >>>>> 4011 4010 4005 4002 4009 4007 4002 4013 4015 4020 4012 4011 4011 4002 >>>>> 4011 >>>>> 4008 4013 4009 4012 4006 4011 4009 4015 4013 4009 4003 4008 4003 4005 >>>>> 4009 >>>>> 4017 4001 4010 4012 4009 4009 4007 4010 4007 4006 4004 4003 4008 4008 >>>>> 4003 >>>>> 4012 4009 4007 4008 4005 4006 4000 3995 4000 4007 4006 4003 4004 4009 >>>>> 4004 >>>>> 4008 4020 4010 4009 4006 4008 4015 4018 4017 4011 4014 4013 4010 4009 >>>>> 4012 >>>>> 4011 4009 4016 4017 4016 4011 4005 4007 4012 4014 4014 4005 4004 3998 >>>>> 4000 >>>>> 4009 4009 4005 3996 4006 3999 4002 4009 4014 4011 4009 4008 4008 4012 >>>>> 4013 >>>>> 4003 4007 4010 4012 4012 4010 4010 4010 4014 4017 4016 4007 4020 4013 >>>>> 4007 >>>>> 4019 4015 4014 4016 4016 4016 4009 4004 4000 4009 4012 4010 4015 4015 >>>>> 4015 >>>>> 4016 4011 4013 4008 4012 4009 4007 4006 4005 4006 4012 4004 4011 4015 >>>>> 4009 >>>>> 4010 4014 4004 3998 4008 4010 4004 4003 4008 4013 4013 4009 4007 4004 >>>>> 4009 >>>>> 4014 4013 4016 4012 4010 4011 4013 4013 4013 4008 4017 4015 4015 4011 >>>>> 4014 >>>>> 4016 4007 4013 4014 4009 3999 4008 4003 4005 4009 4014 4007 4003 3993 >>>>> 3999 >>>>> 3999 4005 4013 4003 4011 4009 4011 4010 4006 4002 4006 3998 4001 4003 >>>>> 4009 >>>>> 4011 4011 4016 4013 4018 4013 4010 4003 4000 4006 4015 4011 4017 4017 >>>>> 4016 >>>>> 4010 4017 4017 4016 4012 4016 4015 4013 4012 4013 4009 4003 4010 4006 >>>>> 4012 >>>>> 4004 4013 4001 4000 4005 3997 4004 4008 4012 4008 4005 3996 4003 3999 >>>>> 4006 >>>>> 4016 4002 4000 4002 4008 4009 4006 3995 4005 4008 4013 4012 4012 4009 >>>>> 4007 >>>>> 4013 4006 4018 4012 4005 4016 4014 4012 4011 4007 4014 4016 4015 4014 >>>>> 4013 >>>>> 4005 4007 4013 4008 4009 4002 4012 4011 4015 4013 4012 4010 4004 4007 >>>>> 4005 >>>>> 4013 4008 4013 4014 4014 4004 4012 4012 4012 4007 4009 4006 4010 4013 >>>>> 4014 >>>>> 4015 4006 4008 4009 4007 4004 4011 4005 4009 4007 4020 4015 4012 4005 >>>>> 4008 >>>>> 4021 4018 4016 4013 4003 4015 4015 4019 4014 4013 4003 4007 4009 4014 >>>>> 4015 >>>>> 3999 4016 4007 4008 4004 4008 4011 4003 4011 4012 4009 4006 4009 4008 >>>>> 4005 >>>>> 4002 4005 4011 4008 4011 4009 4016 4014 4010 4012 4016 4015 4011 4010 >>>>> 4009 >>>>> 4010 4011 4019 4018 4015 4017 4010 4000 4009 4015 4017 4017 4013 4017 >>>>> 4012 >>>>> 4011 4016 4014 3999 4008 4006 4006 4011 4010 4001 4000 4008 3998 4007 >>>>> 4013 >>>>> 4008 4007 4011 4008 4011 4007 4013 4012 4014 4009 4006 4006 4007 4000 >>>>> 4002 >>>>> 4012 4011 4008 4010 4004 4015 4013 4015 4014 4006 4019 4012 4007 4016 >>>>> 4016 >>>>> 4005 4009 4011 4010 4010 4004 4013 4014 4015 4015 4016 4011 4014 4009 >>>>> 4004 >>>>> 4015 4013 4009 4011 4009 4009 4006 4008 4005 3995 4001 4007 4007 4008 >>>>> 4008 >>>>> 4008 4008 4004 4006 4011 4010 4002 4011 4013 4009 4003 4000 4006 4011 >>>>> 4010 >>>>> 4015 4020 4016 4017 4017 4016 4016 4015 4014 4013 4010 4012 4006 4002 >>>>> 4000 >>>>> 4017 4016 4013 4010 4013 4008 4011 4010 4006 4002 4007 4009 4010 4011 >>>>> 4007 >>>>> 4011 4012 4014 4003 4003 4012 4010 4014 4013 4010 4007 3994 4000 4006 >>>>> 4002 >>>>> 3999 4006 4004 4008 4011 4005 4005 4010 4008 4012 4014 4017 4015 4015 >>>>> 4001 >>>>> 4011 4006 4015 4017 4013 4015 4014 4018 4016 4012 4011 4009 4011 4014 >>>>> 4015 >>>>> 4008 4009 4009 4006 4011 4010 4008 4010 4005 4006 4005 4005 4009 4003 >>>>> 4009 >>>>> 4008 4010 4011 4010 4012 4007 4009 4007 4000 4004 4008 4008 4013 4016 >>>>> 4017 >>>>> 4019 4016 4021 4018 4018 4012 4009 4007 4015 4015 4012 4013 >>>>> >>>>> real 0m0.328s >>>>> user 0m0.010s >>>>> sys 0m0.250s >>>>> >>>>> >>>>> That's actually not too bad for opening, and closing the file 1000 >>>>> iterations, then using printf() to display the data to stdout. So, looks >>>>> like 328ms for 1000 iterations on the same adc channel. >>>>> >>>>> debian@beaglebone:~$ uname -a >>>>> Linux beaglebone 4.1.5-ti-rt-r10 #1 SMP PREEMPT RT Fri Aug 14 00:02:42 >>>>> UTC 2015 armv7l GNU/Linux >>>>> >>>>> debian@beaglebone:~$ cat /etc/dogtag >>>>> BeagleBoard.org Debian Image 2015-03-01 >>>>> >>>>> Meaning Wheezy 7.8, and systemd disabled - if the later maters at all. >>>>> >>>>> >>>> -- >>> For more options, visit http://beagleboard.org/discuss >>> --- >>> You received this message because you are subscribed to the Google >>> Groups "BeagleBoard" group. >>> To unsubscribe from this group and stop receiving emails from it, send >>> an email to [email protected] <javascript:>. >>> For more options, visit https://groups.google.com/d/optout. >>> >> >> > -- For more options, visit http://beagleboard.org/discuss --- You received this message because you are subscribed to the Google Groups "BeagleBoard" group. To unsubscribe from this group and stop receiving emails from it, send an email to [email protected]. For more options, visit https://groups.google.com/d/optout.
