Problem with system time in lpc176x bsp

Nick Withers nick.withers at
Sat Dec 19 01:59:12 UTC 2015

On Fri, 2015-12-18 at 16:18 -0300, Marcos Díaz wrote:
> Hi, i'm using c++ chrono to measure a steady signal periods (With
> interrupts), And I see that periodically I have errors of +1ms and
> then of
> -1ms. (I discarded GPIOP interrupts problem) I tried using rtems
> API's
> rtems_clock_get_uptime_nanoseconds
> and then I saw the same errors.
> I'm suspecting of some problem related with interrupts and the
> updating of
> bintime uptime in kern_tc.c related to the simple downcounter ticker
> this
> bsp has.
> Has anybody seen something like this in any other bsp?

Yep, this sounds familiar...

See (pre-timecounter changes) and (post-).
Nick Withers

Embedded Systems Programmer
Department of Nuclear Physics, Research School of Physics and Engineering
The Australian National University (CRICOS: 00120C)

More information about the devel mailing list