Re: [rtl] 32 rt-clock-ticks binned? (fwd)

[Michael Barabanov <baraban@fsmlabs.com>]

Can I see the code please?
What machine is this?

As for rt_get_time, 32 _nanoseconds_ is not that much.

Michael.

bionic@vassalboro.bu.edu (bionic@vassalboro.bu.edu) wrote:
> (Glad to see we're back on line...)
> 
> Hello, I recently switched up to linux2.2.13 & NM rtl-2.0.
> 
> Prior to the upgrade, I had linux2.2.10 & NM rtl-Beta11 running
> a neuron control algorithm, written entirely in 32-bit integer math,
> running at 10kHz.
> 
> With the upgrade, I switched to floating point math, and found input/
> output latencies extending beyond 100us -- which doesn't mesh well
> with 10kHz operation :-(.  Upon switching back to integer math, I find
> that my latency/jitter combo occasionally still extends beyond 100us, even
> when I remove everything computationally expensive from the periodic
> algorithm. (The only thing I'm doing is reading a single channel of a daq
> board - maybe I should check comedi driver???)
> 
> Looking further into the problem, I examine the # of clock ticks I have
> left after each cycle period - it's always a multiple of 32 (from
> rt_get_time). Prior to switching versions, I remember getting single tick
> precision.
> 
> Thought I'd see if any of you had some quick advice, thanks--
> 
> Chuck
> 
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