On the Rpi you can get the current speed of the cpu with the following
command: cat /sys/devices/system/cpu/cpu0/cpufreq/scaling_cur_freq
But beware that the Rpi default uses the on-demand governor for cpu
clocking. This means when you overclock the Rpi and it is idle you get a
lower clock with this command. Only when the CPU is on heavy load it
will get overclocked and the command shows this.
You can also set the threshold when the CPU gets overclocked (in percent
CPU load) with help of the following file. System default is 50% on my
Rpi and 95% on my desktop PC:
/sys/devices/system/cpu/cpufreq/ondemand/up_threshold
Ciao,
Rainer
Am 08.04.2017 um 16:15 schrieb Gene Heskett:
> On Saturday 08 April 2017 09:33:33 sam sokolik wrote:
>
>> does cat /proc/cpuinfo work?
>>
> It doesn't answer the how fast is it now question Sam, only stating the
> present bogomips as 38.something per core.
>
> I have found a line in /boot/config.txt that seems to say its running at
> 700 MHz as default, and could uncomment a line that tells it to run at
> 800 MHz.
>
> But I suspect that is assuming no stickon heat sinks, which I have on it,
> and which aren't noticably warm. With the heat sinks on it, and forced
> fan cooling 1200 MHz. I may clone that u-sd card to use as a recovery,
> then raise that to 800 MHz. Wash, rinse & repeat until its heating
> according to my ir thermometer, to an unhealthy temp. I don't have a fan
> on it. But if it will do 1 GHz, that would be a noticable improvement.
>
> Unfortunately, the spi buss seems to be limited by the slew rate of a
> gpio pin to about 32 MHz. A single spi clock pulse, on a gigahertz
> scope, is a quite good approximation of a classic sine-squared pulse,
> very little evidence of an extended logic 1 to trigger the 7i90, and so
> fussy that the 7i90 will not talk to it if the 10x probe is on the
> signal at lcnc startup. I do not know how, but it might be helped if the
> pi could drive two gpio's for the clocking signal, thereby increasing
> the slew rate by paralleling two gpio's for that function. That of
> course would need a modified adaptor board to combine them. Better yet
> would be a schmidt trigger buffer to steepen up the sides of the pulse,
> and by adjusting the trigger level, widen the pulse by a couple
> nanoseconds. All this of coarse would be before the src termination on
> the adaptor board.
>
> Thank you Sam.
>
> Cheers, Gene Heskett
>
------------------------------------------------------------------------------
Check out the vibrant tech community on one of the world's most
engaging tech sites, Slashdot.org! http://sdm.link/slashdot
_______________________________________________
Emc-users mailing list
Emc-users@lists.sourceforge.net
https://lists.sourceforge.net/lists/listinfo/emc-users
