 | | RCX Programming Questions and Sensor Ideas
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Well, I figure I've been lurking long enough and time to share some questions and thoughts. Question 1: On page 4 of the Technical Reference in the Minstorms SDK there is a reference to a semaphore mechanism. It says: It is possible to implement a (...) (26 years ago, 10-Nov-98, to lugnet.robotics)
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| | Re: RCX Programming Questions and Sensor Ideas
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In article <255199E650C3D11194B...stBuy.com> , Cwikla, Brian <Brian.Cwikla@BestBuy.com> writes (...) An example. Say you want to prevent two tasks from fighting over motor 1. Just insert an instruction in each task before operating the motor to (...) (26 years ago, 10-Nov-98, to lugnet.robotics)
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| | Re: RCX Programming Questions and Sensor Ideas
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(...) This assumes that the check and the set are, together, atomic. Does the SDK document describe what if/why this might be atomic? I haven't had a chance to read it in enough detail to find this answer for myself. -Kekoa (26 years ago, 10-Nov-98, to lugnet.robotics)
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| | Re: RCX Programming Questions and Sensor Ideas
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(...) ...and it would be my sincerest recommendation that you NOT read it, Kekoa. It would be safer from the reverse-engineering standpoint that you NOT use this SDK in any manner. *I* can read it, though <g>, and I can find nothing that indicates a (...) (26 years ago, 10-Nov-98, to lugnet.robotics)
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| | Re: RCX Programming Questions and Sensor Ideas
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(...) Check and set do not have to be atomic, they have to be ordered. The sequence is: Check all flags, when clear, set our flag, check all flags again, if only ours is set, do stuff. 1. You can dedicate a task to managing semaphores. I described (...) (26 years ago, 11-Nov-98, to lugnet.robotics)
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| | SDK?
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Cwikla, Brian wrote in message <255199E650C3D11194B...uy.com>... (...) Where do you purchase this SDK? (...) (26 years ago, 11-Nov-98, to lugnet.robotics)
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| | Re: SDK?
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(...) You have it already. It is the OCX. Cheesy? Perhaps. You will have an infinitely better API available in short order. -Kekoa (26 years ago, 11-Nov-98, to lugnet.robotics)
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| | Re: RCX Programming Questions and Sensor Ideas
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In article <199811102221.OAA071...ford.EDU>, Kekoa Proudfoot <kekoa@Graphics.Stanford.EDU> quotes and writes (...) You are right, of course. (...) If it does I haven't found it. (26 years ago, 11-Nov-98, to lugnet.robotics)
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| | Re: RCX Programming Questions and Sensor Ideas
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(...) It isn't guaranteed to work, either, though it is likely to in the end. This is because two processes can conspire to always have r31 == 2 when you test for r31 == 1. Cheers, Ben. (26 years ago, 11-Nov-98, to lugnet.robotics)
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| | Re: RCX Programming Questions and Sensor Ideas
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In message <3648D155.FF4306@alu...ucsc.edu>, Joshua Delahunty <lugnet.robotics@lugnet.com> writes (...) RECEIVED is spelt wrong in the Spirit.OCX software too. :-) I would like to add though that I was impressed with the high quality of the manual. (26 years ago, 11-Nov-98, to lugnet.robotics)
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| | Re: RCX Programming Questions and Sensor Ideas
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(...) Oops. I don't know how the scheduler in the RCX works. It might execute 1 opcode from each task in order. If 2 tasks get in sync, then they will never leave the semaphore code as written. Here's a fixed version. I added a random backoff. (...) (...) (26 years ago, 11-Nov-98, to lugnet.robotics)
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| | Re: RCX Programming Questions and Sensor Ideas
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(...) Paul, Are you sure you want to sleep before decrementing r31? As written, r31 is always >= 1 during the sleep -- which prevents any other tasks from obtaining a lock on the resource during this sleep time. In other words, once any two tasks (...) (26 years ago, 11-Nov-98, to lugnet.robotics)
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| | Re: RCX Programming Questions and Sensor Ideas
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(...) I think "oops" applies in this case. Your fix looks correct. (...) It doesn't have to be random, just each task needs a different delay. This is easy, since each task has to run its own version of the code. For task 3 insert 3 noops, for task (...) (26 years ago, 11-Nov-98, to lugnet.robotics)
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| | Re: RCX Programming Questions and Sensor Ideas
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(...) Does that support an arbitrary number of tasks? If there are n tasks numbered 1 to n, and task k delays for k cycles on failure, I think you still have to be careful to make sure that the number of tasks n is smaller than the loop overhead h (...) (26 years ago, 11-Nov-98, to lugnet.robotics)
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| | Re: RCX Programming Questions and Sensor Ideas
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I hope someone reads this reply to a reply to a very OLD message. I've been lurking for almost a month and, during a search, I found a thread I can expand. (...) [snip] (...) It is more difficult than this to recognize speech, but it can be done. (...) (25 years ago, 27-Aug-99, to lugnet.robotics)
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| | Re: RCX Programming Questions and Sensor Ideas
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I think it would be more interesting to synthesise human voice, that is to make the RCX speak! :-] (...) [ mailto:lau@mail.telepac.pt ] [ (URL) ] -- Did you check the web site first?: (URL) (25 years ago, 28-Aug-99, to lugnet.robotics)
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| | Re: RCX Programming Questions and Sensor Ideas
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(...) Maybe AS interesting.. I also have a TI Speak 'N' Math that I would like to rip the guts out of, too. Has anyone hacked a Speak 'N' Whatever before? Is it worth it? Amos Turn my address umop episdn to shake out the spamcake. (...) (25 years ago, 29-Aug-99, to lugnet.robotics)
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