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(...) Actually, something like this has been documented and done by Pedersen, Christensen, Rasmussen ("Prioritized Interrupts in LegOS"). They actually document the problem of sensor misses related to task management, significantly reducing the (...) (23 years ago, 5-Feb-02, to lugnet.robotics.rcx.legos)
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| | Re: multiplexor and legOS
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(...) Most people's legOS kernels will be compiled so msleep uses wait_event. I haven't looked at the code, but my understanding of how wait_event works is that whenever that thread becomes eligible to execute, your even function is called. (...) (23 years ago, 5-Feb-02, to lugnet.robotics.rcx.legos)
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| | Re: multiplexor and legOS
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Try the following code fragments. [Change to fixed spacing font so that it reads easily.] You should be able to find what you need. "Mark Falco" <> wrote in message news:Gr1MBL.Dop@lugnet.com... (...) <<..snip..>> (...) These are code fragment for (...) (23 years ago, 5-Feb-02, to lugnet.robotics.rcx.legos)
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| | Re: multiplexor and legOS
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Ok, my last port didn't make much sense let me try that again. for an active sensor ds_handler will periodically power the sensor off to read the value. The standard firmware does this to but at a different interval. I'm wondering if this is part of (...) (23 years ago, 5-Feb-02, to lugnet.robotics.rcx.legos)
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| | Re: multiplexor and legOS
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Since I'm now fairly sure that i've got the timing taken care of I'm wondering if the power cycling that ds_handler does is somehow causing the problem? I thought I might take control of this stuff in my test code. I assume if I set the sensor for (...) (23 years ago, 5-Feb-02, to lugnet.robotics.rcx.legos)
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| | Re: multiplexor and legOS
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(...) It looks like the semaphore task_sm should prevent another task from being scheduled if I hold it for the length of the train. I've now tried this as well as incresing the timeslice to 100ms. It looks better but still is not consistent. Since (...) (23 years ago, 5-Feb-02, to lugnet.robotics.rcx.legos)
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| | Re: multiplexor and legOS
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(...) Not bad. But as you say, still vulnerable to the task switching problem. (...) Instead of resorting to that, maybe there is a way to freeze task switching during critical operations. When I owned and programmed the AmigaOS (don't laugh :), (...) (23 years ago, 5-Feb-02, to lugnet.robotics.rcx.legos)
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| | Re: multiplexor and legOS
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#include <sys/time.h> void systime_set_timeslice (unsigned char slice); include/sys/time.h:43-45: #ifdef CONF_TM #define TM_DEFAULT_SLICE 20 file://!< default multitasking timeslice #endif hope that helps, Albert "Michael J Ash" (...) (23 years ago, 4-Feb-02, to lugnet.robotics.rcx.legos)
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| | Re: multiplexor and legOS
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(...) I agree about the cause for the msleep granularity, I'd seen the same stuff in tm and assumed that would cause the problem. Sorry my last note was a little unclear, I tried msleep and delay but am now using my own function which seems to (...) (23 years ago, 4-Feb-02, to lugnet.robotics.rcx.legos)
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| | Re: multiplexor and legOS
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(...) I don't know about this 20ms granularity and how delay() is going to be any better. Here's the code for each function: //! delay execution allowing other tasks to run. /*! \param msec sleep duration in milliseconds \return number of (...) (23 years ago, 4-Feb-02, to lugnet.robotics.rcx.legos)
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