if you help me*
Terça-feira, 9 de Dezembro de 2014 12:01:30 UTC, Luciano escreveu:
>
> Hey TFJ,
>
> I did this way and I would be glad of you helped me in this question. I
> have installed Libpruio0.0.2, and I wrote a simple code just to read the
> ADC value (Value[1]) from the output port P9_14 to see it commute.(I don't
> need all that libraries, but they are there for further algorithms). In the
> circuit I added a voltage divider with two 10k resistors, to get about 1,7V
> to not cross 1,8V.
>
> -----------------------
>
> /*
> Test ADC max sample rate
> Libpruio 0.0.2
> Compile by:
> gcc -Wall -o ReadADC ReadADC.c /usr/local/lib/freebasic/fbrt0.o -lpruio
> -L"/usr/local/lib/freebasic/" -lfb -lpthread -lprussdrv -ltermcap -lsupc++
> */
> #define _GNU_SOURCE 1
> #include "stdio.h"
> #include <termios.h>
> #include <unistd.h>
> #include <errno.h>
> #include <sys/types.h>
> #include <sys/time.h>
> #include "../c_wrapper/pruio_c_wrapper.h"
> #include "../c_wrapper/pruio_pins.h"
> #include <stdlib.h>
> #include <stdbool.h>
> #include <time.h>
>
> #define P1 P9_14
>
> int main(int argc, char **argv)
> {
>
> PruIo *io = pruio_new(0, 0x98, 0 ,1);
> pruio_config(io, 0, 0x1FE, 0, 4, 0);
>
> if (io->Errr) {
> printf("initialisation failed (%s)\n", io->Errr);}
>
> if (pruio_gpio_set(io, P1, PRUIO_OUT1, PRUIO_LOCK_CHECK)) {
> printf("failed setting P1 (%s)\n", io->Errr);}
>
> if (pruio_config(io, 0, 0x1FE, 0, 4, 0)) {
> printf("config failed (%s)\n", io->Errr);}
>
> while (1)
> {
> if (io->Value[1] < 25000 )
> {
> pruio_gpio_out(io, P1, 1);
> printf(" %6d ", io->Value[1]);
> printf("\n");
> }
> else
> {
> pruio_gpio_out(io, P1, 0);
> printf(" %6d ", io->Value[1]);
> printf("\n");
> }
> }
> pruio_destroy(io);
> return 0;
> } // end of main
>
> ---------------------
> The thing is that I'm only getting about 10kHz. It is normal to just get
> this sample rate?
>
>
> <https://lh3.googleusercontent.com/-uO0ixAS_O6Y/VIbijDNYsYI/AAAAAAAAACE/W42721NvvEU/s1600/20141209_111337.jpg>
>
> Thanks in advance.
> Luciano.
>
>
> Terça-feira, 4 de Novembro de 2014 16:57:48 UTC, TJF escreveu:
>>
>> Hello jleb!
>>
>> Sorry for the late answer. I did some testing, meanwhile, and it seems
>> that you're right. The ADC subsystem is clocked by CLK_M_OSC directly at 24
>> MHz. (First, I thought there's an additionaly pre-scaler in the PRCM.)
>>
>> Find attached a libpruio measurement from four channels, connected to a
>> PWM output by different voltage dividers. The PWM frequency and the
>> sampling rate are configured that way that a complete period plus two
>> pixels get shown in the window. The result is as expected, and even if I
>> increase the frequencies, all looks good up to a sampling rate of 200 kHz.
>>
>>
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