 | | Trains, DCC, and pbForth
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All, As I've mentioned before, I have a version of pbForth firmware for the RCX that allows you to control trains modified with DCC controllers. The benefit of pbForth is that you can write, test, and debug your application interactively using (...) (22 years ago, 21-Nov-03, to lugnet.trains, lugnet.robotics.rcx.pbforth)
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| | Re: Ultrasonic proximity sensor
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(...) Right. The word ultrasonic means "higher than sonic" or above the 40KHz top end of the audible range. These are sonic proximity sensors, FWIW. - Chris. (22 years ago, 21-Nov-03, to lugnet.robotics, FTX)
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| | Re: Ultrasonic proximity sensor
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(...) Many different ones, ranging from clearly audible to much more than 40kHz. Depends on what they're doing. -- -- Open Forge, LLC 24/365 Onsite Support for PCs, Networks, & Game Consoles 512-695-4126 (Austin, Tx.) help@open-forge.com (...) (22 years ago, 21-Nov-03, to lugnet.robotics)
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| | Re: Ultrasonic proximity sensor
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(...) Indeed. 24khz for audio is too low. It should be at least 40khz if it's using sound. (btw, what frequencies do bats use?) >> Mark (22 years ago, 21-Nov-03, to lugnet.robotics)
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| | Re: Are there GOTO statements in NQC?
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(...) The purpose of garbage collection is to remove resources from use when they are not going to be used anymore. It covers a variety of issues, some you've each touched on. I suggest as a start, Garbage Collection: Algorithms for automatic (...) (22 years ago, 21-Nov-03, to lugnet.robotics)
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| | Re: Are there GOTO statements in NQC?
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(...) Um, not exactly. Structured programming is about taking a high level problem, breaking it down into logically related modules (using as much reuse as possible) and then breaking those modules down as well, and so on. It's about being cognizent (...) (22 years ago, 21-Nov-03, to lugnet.robotics)
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| | Re: Are there GOTO statements in NQC?
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Don't know about C/C++, but IIRC in Java the garbage collector destroys objects not when they are out of scope, nor when their creator function exits. It destroys them when the object is no longer referenced by any threads. That is to say, if (...) (22 years ago, 21-Nov-03, to lugnet.robotics)
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| | Re: Are there GOTO statements in NQC?
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(...) I've been coding since about '81, too. Big deal. (...) Well, yes, by transforming it into a while loop with a state variable representing what would otherwise be the execution counter. While this is a provable transformation, it doesn't (...) (22 years ago, 21-Nov-03, to lugnet.robotics)
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| | Re: Are there GOTO statements in NQC?
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As a computer science software engineer i work since 1984. My university studies before (Hamburg, Germany) taught me, that science had proved: any program using a goto statement can easily be transformed into a structured program. Remember, that (...) (22 years ago, 21-Nov-03, to lugnet.robotics)
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| | Re: Are there GOTO statements in NQC?
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(...) *snicker* I'm surprised you used C as one of your example languages, then. Anyway, not all of us are so lucky as to be able to choose a language where you can hide all your cleanup code like that. As a personal issue, I find such cleanup (...) (22 years ago, 21-Nov-03, to lugnet.robotics)
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| | Re: Ultrasonic proximity sensor
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(...) back up alarms for dogcatchers and photographers... (22 years ago, 20-Nov-03, to lugnet.robotics)
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| | Re: Are there GOTO statements in NQC?
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(...) Which is why we have C++. With memory constructors and destructors, quite complex resources can be automatically and cleanly free'd up on exit from a function. ---...--- Steve Baker ---...--- HomeEmail: <sjbaker1@airmail.net> WorkEmail: (...) (22 years ago, 20-Nov-03, to lugnet.robotics)
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| | Re: Are there GOTO statements in NQC?
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Rob Limbaugh wrote: > I find that GOTO is a very handy way to bypass code to test some > alternate code in high-level languages. Nope - that's why we have #ifdef/#endif > It is also a command that is > easy to match to a machine language code of (...) (22 years ago, 20-Nov-03, to lugnet.robotics)
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| | Re: Ultrasonic proximity sensor
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(...) sorry to dissappoint you but i made that up just for a laugh. i'm glad you got a laugh out of it! Michael (22 years ago, 20-Nov-03, to lugnet.robotics)
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| | Re: Are there GOTO statements in NQC?
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(...) This exact same argument can be applied to high-level languages where you dynamically allocate memory or other resources that need to be released before leaving the function. While I agree that forcing people to have only one exit point at all (...) (22 years ago, 20-Nov-03, to lugnet.robotics)
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| | Re: Ultrasonic proximity sensor
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(...) Seriously? That's hilarious. -- -- Open Forge, LLC 24/365 Onsite Support for PCs, Networks, & Game Consoles 512-695-4126 (Austin, Tx.) help@open-forge.com irc.open-forge.com Hangar 18 Open Source Distributed Computing Using Plan 9 & Linux (...) (22 years ago, 20-Nov-03, to lugnet.robotics)
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| | RE: Are there GOTO statements in NQC?
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I find that GOTO is a very handy way to bypass code to test some alternate code in high-level languages. It is also a command that is easy to match to a machine language code of various processor types. In writing batch scripts on Windows (...) (22 years ago, 20-Nov-03, to lugnet.robotics)
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| | Re: Ultrasonic proximity sensor
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(...) The frequency at which air is best matched is about 40kHz, several things with this: - low resolution because of the low frequency - going to take more power to get a given range of detection than using a commercial grade unit (works at 40kHz) (...) (22 years ago, 20-Nov-03, to lugnet.robotics)
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| | Ultrasonic proximity sensor
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Mindsensors Has recently developed a Ultrasonic distance sensor, which uses 24 KHz ultrasonic wave for distance mesurements. If your are interested visit us at www.mindsensors.com/uspd.htm www.mindsensors.com Mindsensors Robotics (22 years ago, 20-Nov-03, to lugnet.robotics)
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| | Re: Are there GOTO statements in NQC?
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(...) The thing everyone has forgotton about the "one exit point" rule is that it applies to MACHINE CODE PROGRAMMING - not high level languages. This single misunderstanding has resulted in more convoluted and illegible code than I care to (...) (22 years ago, 20-Nov-03, to lugnet.robotics)
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