On 11 Apr 2009 at 5:45, Len Shelton wrote:
> > I am unsure of some of the syntax, and this is untested. I will be > back in > the shop in a few hours and will be able to try it out. When I'm testing I do a bit at a time if possible... > > Do you see anything blatantly wrong with any of my code? > > Do I have to name every signal, particularly the ones to the inputs > of the > logic gates? In other words is: Yes each signal needs a unique name. > > net home1 parport.0.pin-10-in and2.0.in0 > > the same as: > > net parport.0.pin-10-in and2.0.in0 > > ? > > >Len > > > > > -----Original Message----- > From: Stephen Wille Padnos [mailto:spad...@sover.net] > Sent: Friday, April 10, 2009 10:32 AM > To: Enhanced Machine Controller (EMC) > Subject: Re: [Emc-users] syncing two motors to one axis > > Len Shelton wrote: > > >Jon and Rob, > > > >You guys obviously know a lot more about the inner working of HAL > than I. I > >am still no closer to understanding what lines of code I need to > put into > my > >HAL file. > > > >Can you please translate this simple boolean text notation... > > > > home_en1 = dir OR NOT home1 > > home_en2 = dir OR NOT home2 > > step_1 = step AND home_en1 > > step_2 = step AND home_en2 > > home = ( ( home1 AND home2 ) AND NOT dir ) OR ( ( home 1 OR > home2 ) > > AND dir ) > > > >...to actual HAL syntax. > > > > > Well, I'll point you in the right direction anyway :) > > First off, the manual sections on HAL are quite good - you should > (re) > read them. > > I'm not sure your logic is correct. I don't believe that the home > signal should depend on the DIR signal. I'm pretty sure that home > should just be (home1 AND home2). If both switches are closed, then > you're home regardless of which way the DIR line is pointing. > > Looking at your logic description, these things are apparent: > 1) there are four occurrences of the word "OR" > 2) there are five occurrences of the word "AND" > 3) there are three occurrences of the word "NOT". Luckily, all of > the > signals that get inverted come from I/O (if you're using my HOME > equation), which provides both a normal and inverted output to HAL, > so > you don't actually need any NOT functions > 4) all of the logical operations are operating on exactly two items > (ie, > there is no "a OR b OR c") > 5) This is for only one axis (phew!) > 6) Changing the home equation to home=(home1 AND home2) reduces the > number of gates to 2x OR, 3x AND, and zero NOT (since you can use > the > inverted home1 and home2 inputs) > > Here's how to get 3 AND "gates": > loadrt and2 count=3 > > This will give you 3 two-input AND gates. Each one has a function > which > needs to be added to your base thread, before the motion controller > runs. This will be a little tricky to get right, since you want to > read > inputs before doing the logic operations, and you want results to > propagate through the logic caluclations correctly, you have to > think > about which "inputs" get connected to which logic elements, and the > order in which they are evaluated. I'd suggest drawing this out on > paper, using a grid. Start with the inputs on the left, run them > towards the right, using columns with only one gate in each logic > path. > When you add functions to the HAL thread, start at the top left and > add > the first column of functions from top to bottom. Then move over > one > column to the right and add those functions from top to bottom. > > This is the logic I would use, which may make the order the > functions > need to run mode obvious: > step1 = step AND (dir OR home1-invert) > step2 = step AND (dir OR home2-invert) > home = (home1 AND home2) > > Sorry for the long-winded and not very specific post. Hope it > helps. > - Steve > > > -------------------------------------------------------------------- > -------- > -- > This SF.net email is sponsored by: > High Quality Requirements in a Collaborative Environment. > Download a free trial of Rational Requirements Composer Now! > http://p.sf.net/sfu/www-ibm-com > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > > > -------------------------------------------------------------------- > ---------- > This SF.net email is sponsored by: > High Quality Requirements in a Collaborative Environment. > Download a free trial of Rational Requirements Composer Now! > http://p.sf.net/sfu/www-ibm-com > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > ------------------------------------------------------------------------------ This SF.net email is sponsored by: High Quality Requirements in a Collaborative Environment. 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