 | | Re: threads - bug in the firmware?
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Hi Mike, your problem is not because of an error in legOS. But what you do is that you start your subroutines and then you leave main()! Leaving main means that all your allocated memory is freed. The following will do the job: ---...--- cut here (...) (23 years ago, 17-Jan-02, to lugnet.robotics.rcx.legos)
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| | Re: threads - bug in the firmware?
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;-) That worked a treat, thanks Michael. (thanks for the other little corrections in the code too). mike (...) Mike, (...) your subroutines and then you leave main()! Leaving main means (...) memory is freed. The following will do the job: (...) (...) (23 years ago, 17-Jan-02, to lugnet.robotics.rcx.legos)
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| | Re: threads - bug in the firmware?
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(...) Note also since bumper_task() is an infinite loop, and you never use pid1, you could save one thread by doing this: int main(int argc, char *argv[]) { pid2 = execi (&left_task, 0, NULL, PRIO_NORMAL+2, DEFAULT_STACK_SIZE); pid3 = execi (...) (23 years ago, 17-Jan-02, to lugnet.robotics.rcx.legos)
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| | Re: threads - bug in the firmware?
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Hi Ross (...) you (...) What are the advantages and disadvantages of this method as opposed to the one I used? mike (23 years ago, 18-Jan-02, to lugnet.robotics.rcx.legos)
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| | Re: threads - bug in the firmware?
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(...) I would strongly suggest changing this to while(1) msleep(bignumber);. Otherwise you're hogging the processor doing nothing important, which could do bad things to any compute-intensive tasks you may have going. It'll also use slightly less (...) (23 years ago, 18-Jan-02, to lugnet.robotics.rcx.legos)
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| | More on threads
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(...) Of course you are right. I think it is a bad programming style not to give your program the ability to terminate but to run in an endless loop. But what is the penalty for this bad style? I've done some investigations and here are the results: (...) (23 years ago, 18-Jan-02, to lugnet.robotics.rcx.legos)
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| | Re: More on threads
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(...) ability to terminate but to run in an endless loop. But This is not true of an embedded system though which will have to run 'forever'. (...) priority of NORMAL+4. So, the (...) any time slice at all. NO time slice or just a very small chunk (...) (23 years ago, 19-Jan-02, to lugnet.robotics.rcx.legos)
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| | Re: More on threads
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(...) Digging through tm.c gave me the impression, that main will indeed get no time slice. So I wrote another test program: ---...--- #include <conio.h> #include <unistd.h> pid_t worker; int work_task(int argc, char *argv[]); int main() { int i; i (...) (23 years ago, 19-Jan-02, to lugnet.robotics.rcx.legos)
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| | Re: More on threads
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(...) I recall that legOS's priority model is pretty rigid. If a thread with a higher priority never yields, threads with lower priority will never get any time. When I write legOS programs, I generally just have everything run at PRIO_NORMAL. That (...) (23 years ago, 19-Jan-02, to lugnet.robotics.rcx.legos)
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| | Re: threads - bug in the firmware?
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(...) Advantage: Less memory used (each thread needs a block of memory in the kernel, I'm at work & can't remember the struct name off hand). In the case under discussion, this doesn't make much difference, but in a large project, memory use can (...) (23 years ago, 21-Jan-02, to lugnet.robotics.rcx.legos)
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