[ECOS] change of clock resolution

[ECOS] change of clock resolution

[Micha&lstrok]

I asked how to change real time clock resolution on PC i386 platform.
I received the answer with advice to change CYGNUM_HAL_RTC_PERIOD. I've
changed CYGNUM_HAL_RTC_PERIOD, CYGNUM_HAL_RTC_NUMERATOR and
CYGNUM_HAL_RTC_DENOMINATOR in "hal_i386_pc.h" to get larger resolution, but
it had no effect (100 ticks is still equal to 1sec). Is it possible that
clock resolution is "unchangeable" at PC platform?

What I'm doing wrong?

--
Michal Olenczuk
POLAND
mailto: olenczuk@rts.com.pl
tel. 0604091867

RE: [ECOS] change of clock resolution

[Andy Simpkins]

Someone shout out and correct me if I am wrong but the values you have
changed will have NO effect on the clock interval... if you have a timer
ticking at 100Hz it will remain ticking at 100Hz after you change these
values.  what will have changed is eCos' perception of time (not the real
time).

If you want your clock ticks to be 10 times faster you need to change the
timer settings found in hal_clock_initialize <platform>_misc.c (or the
appropriate routine for your build)

Andy

-----Original Message-----
From: ecos-discuss-owner@sources.redhat.com
[ mailto:ecos-discuss-owner@sources.redhat.com]On Behalf Of Micha&lstrok; Ole&nacute;czuk
Sent: 24 April 2001 13:15
To: ecos-discuss@sources.redhat.com
Subject: [ECOS] change of clock resolution


I asked how to change real time clock resolution on PC i386 platform.
I received the answer with advice to change CYGNUM_HAL_RTC_PERIOD. I've
changed CYGNUM_HAL_RTC_PERIOD, CYGNUM_HAL_RTC_NUMERATOR and
CYGNUM_HAL_RTC_DENOMINATOR in "hal_i386_pc.h" to get larger resolution, but
it had no effect (100 ticks is still equal to 1sec). Is it possible that
clock resolution is "unchangeable" at PC platform?

What I'm doing wrong?

--
Michal Olenczuk
POLAND
mailto: olenczuk@rts.com.pl
tel. 0604091867

Re: [ECOS] change of clock resolution

[Jonathan Larmour]

Andy Simpkins wrote:
> 
> Someone shout out and correct me if I am wrong but the values you have
> changed will have NO effect on the clock interval... if you have a timer
> ticking at 100Hz it will remain ticking at 100Hz after you change these
> values.  what will have changed is eCos' perception of time (not the real
> time).
> 
> If you want your clock ticks to be 10 times faster you need to change the
> timer settings found in hal_clock_initialize <platform>_misc.c (or the
> appropriate routine for your build)

No the PERIOD is what is used to program the clock and is passed to
hal_clock_initialize by the kernel.

Jifl
-- 
Red Hat, Rustat House, Clifton Road, Cambridge, UK. Tel: +44 (1223) 271062
Maybe this world is another planet's Hell -Aldous Huxley || Opinions==mine

RE: [ECOS] change of clock resolution

[Andy Simpkins]

thanks

-----Original Message-----
From: jlarmour@cambridge.redhat.com
[ mailto:jlarmour@cambridge.redhat.com]On Behalf Of Jonathan Larmour
Sent: 24 April 2001 17:48
To: Andy.Simpkins@TardisMobile.com
Cc: ecos-discuss@sources.redhat.com
Subject: Re: [ECOS] change of clock resolution


Andy Simpkins wrote:
> 
> Someone shout out and correct me if I am wrong but the values you have
> changed will have NO effect on the clock interval... if you have a timer
> ticking at 100Hz it will remain ticking at 100Hz after you change these
> values.  what will have changed is eCos' perception of time (not the real
> time).
> 
> If you want your clock ticks to be 10 times faster you need to change the
> timer settings found in hal_clock_initialize <platform>_misc.c (or the
> appropriate routine for your build)

No the PERIOD is what is used to program the clock and is passed to
hal_clock_initialize by the kernel.

Jifl
-- 
Red Hat, Rustat House, Clifton Road, Cambridge, UK. Tel: +44 (1223) 271062
Maybe this world is another planet's Hell -Aldous Huxley || Opinions==mine