Re: [ECOS] changing the length of a tick

[Jonathan Larmour <jlarmour at redhat dot com>]

Tom Coremans wrote:
> 
> Hi,
> 
> I`m trying to change the length of tick  to 50 milli seconds with the
> following code:
> 
> ________________________
> cyg_handle_t rclock;
> cyg_resolution_t res;
> cyg_uint32 nsec_per_tick = 50000000;
> res.dividend = nsec_per_tick;
> res.divisor = 1;
> rclock = cyg_real_time_clock();
> cyg_clock_set_resolution(rclock,res);
> _____________________
> 
> but when I run a test this doesn`t seem to work.
> It seems there are still 100 ticks in a second, the default
> configuration.
> 
> Does anybody know whats wrong with this?

The configured resolution has to reflect what the clock actually does. In
this case there is nothing that actually tells the clock hardware to do
anything other than 100 ticks per second (10000000 ns/tick). It's just that
now eCos will *think* when it got a tick that is 20 ticks per second.

Look at how the kernel uses the HAL to configure the real hardware and do
the same thing.

Jifl
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