Re: [Emc-users] Thank you.
2012/4/26 Gabriel Willen gabewil...@gmail.com: All though my end goal will be my own motion controller with some of Linux cnc components. I also am using LinuxCNC for industrial machines and one thing I would like to add is that I do not see a point to go this route - developing Your own cnc controller. You already can easily create Your own GUI, so that You have Your own looks of the application and You also can set the name of the GUI to something Your own, like name of company or Your trademark. That is the only thing I want to customize in LinuxCNC - to set up my name, trademark so that any third party person, who sees the machine for the first time, can see, who has made it. What I am trying to say is that creating Your own cnc controller will be reinventing the wheel. If there are any downsides currently in the application, I bet everyone would be happy, if You could help fixing them in master branch rather than in Your own branch (well, it would be fine, if You had it in Your branch and made it available to public). The project would benefit very much from that. And in Your own cnc controller You most probably will not be able to get some features or bugfixes from master branch in an easy and convenient way (except those elements that are unchanged). So I do not see what is the benefit to diverge from master branch - if it is based on it, You still cannot make it proprietary. But creating yet another opensource product - well, I think CAM applications is one very nice example, where fragmentation is very high, but usable products are... well, none? If You will have Your own cnc controller, You will have to take a [very very] long path to gain market recognition for it beyond Your friend, colleagues and clients that would use Your machines. If You stick with LinuxCNC, part of that path has already been walked and the rest of it will be shorter due to cummulative efforts of all the users together. I want to seperate the user space and realtime environment in seperate hardware. If I understand the question correctly, You already can run LinuxCNC on a headless box without any graphical frontend loaded and control it from other PC. And there are several options for manufacturers of FPGA cards, which can take on some of the realtime tasks. So to large extent it is already there. And You are always welcome to add something more to it :) Viesturs -- Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Bldc_Hal
On 26.04.12 09:31, Gabriel Willen wrote: Andy would you care to enlighten me a little on your sign lookup table? I have an xmega laying around I have been playing with. I have it decoding and picking up the hall positions. But I'm not grasping the sign lookup table. I have read a half a dozen articles on it. In sure I will figure out, I always do but I figured maybe you could help. Also I thought about porting your bldc component, removing the real time and Hal includes and trying to make it work. But honestly I don't need all the wonderful bells and whistles you have included in yours. Just in case it's interesting, there is a much more compact method than trigonometric lookup tables, and it generates sine and cosine simultaneously, with tangent costing only an additional division, IIRC. It is called CORDIC, and wikipedia has a good go at explaining it: http://en.wikipedia.org/wiki/Cordic I haven't stopped to wade through that, but my recollection, from nearly 40 years back, is that we start with a short table of binary weighted table of arctangents, e.g artan(45°), artan(22.5°), artan(11.25°), ... down to the desired resolution. Twenty table entries gets us to 6 decimal digit angle resolution¹, because any angle can be arrived at by adding or subtracting the twenty values. (Plus some fiddling.) But why binary weighted? Because now the multiplication in the CORDIC algorithm reduces to a shift. (Queue angel chorus thunder roll.) The whole thing runs like greased lightning, even on a microcontroller. (It was used on digital calculators 40 years ago, and they nibbled at maths.) I have a CORDIC algorithm implementation, but it's in TMS9900 assembler. digression Prior to its extinction, that processor had a programmable shift operation, so it did a *2^n in one hit, rather than repeated one bit shifts, making it ideal for this kind of stuff. (Mind you, an xmega would still be one to two orders of magnitude faster than the TMS9900, which had only 3 on-chip registers. The 16 user registers were memory resident, and so could be bank switched, just by changing the Workspace Pointer to use another part of memory, with the previous WP,PC,ST registers replicated in the new R13,R14,R15.) /digression Anyway, it wouldn't be that hard to translate to AVR assembler or C. Must try that one day. Erik ¹ But a dozen table entries use up a 16 bit sine value range, so one might settle for a slightly shorter table than that. -- How many seconds are there in a year? If I tell you there are 3.155 x 10^7, you won't even try to remember it. On the other hand, who could forget that, to within half a percent, pi seconds is a nanocentury. -- Tom Duff, Bell Labs -- Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] Bldc_Hal
On 27 April 2012 02:38, Gabriel Willen gabewil...@gmail.com wrote: Yes i have seen that video, i actually commented on it asking for the sketch. I haven't heard from him though so i assume he either doesn't want to share it or hasn't checked the comments yet. It seems to have been flagged as spam, so I didn't get a notification. I will see if I can find the sketch, though it is quite possible I din't keep that one. The vast majority of the sketch is concerned with generating a sine wave and measuring voltages to get the feedback from the Resolver. -- atp The idea that there is no such thing as objective truth is, quite simply, wrong. -- Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] the state of the Wiki
On 4/18/2012 1:45 PM, Przemek Klosowski wrote: On Tue, Apr 17, 2012 at 11:18 AM, Kent A. Reedkentallanr...@gmail.com wrote: Speaking of the Wikinudge, nudge, wink, wink, it could use a lot more editorial work. Looking at the Recent Changes listing, I see the usual few suspects making progress but there is a lot of work left. Back in January, after the decision was announced to rebrand our work LinuxCNC, I spent time under my SourceForge pseudonym CNCDreamer trying to fix up the most egregious instances of EMC2 but had to leave a number of pages marked as in progress because they required technical changes I felt unprepared or even unqualified to make. Looking now, I see many of the same pages haven't been touched since. There are a number of pages that are terribly stale and the organization of the home page is trending toward chaos. Try to read it like you were new to LinuxCNC and see what you make of it. I wish I were in a position to do more of what needs to be done, but recent challenges at home make a concerted effort impossible. I'm lucky You're very persuasive--the can you make a list of pages that require most urgent update, in your opinion? Gentle persons: I don't have the time to do a quality job of this but just to throw out some items that strike me... [disclaimer: I realize that a wiki is by definition the antithesis of order, since anything can be inserted anywhere any time, and that the only criterion for anyone making a contribution is that they feel motivated to do so. Nevertheless, I think it is incumbent on us to keep our wiki relevant to newbies because it is like to be the first place they look. Sure, we have written a boatload of manuals but, honestly, don't most people go to a wiki first in hopes of not having to read hundreds of pages of manuals?] I'll assert without proof that the first places on the wiki a newcomer would look are News and the first two major divisions of the ToC, namely About LinuxCNC and Getting Started. To my way of thinking News suffers from two problems: 1) a lack of posting dates or even an indication that it reads from newest to oldest, and 2) a lack of parallelism---the announcements regarding the release of 2.5 and 2.4.7 are interlineated (thanks, Michael!) with a much more obscure announcement regarding versions of Ubuntu. Section 1. About LinuxCNC is more a discussion of the evolution of LinuxCNC from EMC1 than a discussion of the features of LinuxCNC, which is what I believe a newcomer would be likely to expect. Some of this stuff is as old as my grandkids and it's less interesting. Here's a good place to outline why people would want to use LinuxCNC. Screenshots is pretty good but probably needs a comment about many of the screens showing their EMC2 heritage. Videos is what it is. I haven't checked it lately for broken links but I believe there is at least one but probably only a few. Case Studies, same comments as the two above. Comparisons implies much but yields little. I'd think a newcomer on a budget would expect to see something about LinuxCNC vs Mach3 and any serious CNC buff would expect to see more about other industrial controllers than the existing one-line entry concerning an unknown version of EMC versus Fanuc11m. I'm just saying OldReleases and Released need a little fixing up. The former means releases prior to 2.4 and the latter now means 2.4.x and 2.5. Section 2. Hardware Requirements needs work to bring it up to current technology, both in terms of LinuxCNC and in terms of platforms. Since the following subsection LinuxCNC Supported Hardware also uses the word Hardware but in the sense of interfaces, I think it would be useful to choose the title Computer Requirements instead. LinuxCNC Supported Hardware is probably as good as it gets given the flux in the marketplace. Latency Test is a conundrum for me. I can't figure whether it would be better to sort it on brandname or on date of the system. Right now the table seems a mixture of top posting, bottom posting, and alphabetical posting. Still, I wouldn't want to throw the baby out with the bathwater. Installing LinuxCNC is where I crashed and burned during the great name change because the token emc is so well embedded in the names of directories, scripts, what have you. I think an executive decision has to be made. Is this page to support both installation of LinuxCNC 2.5 and also EMC2 2.4.7 and earlier? Then I believe the page has to be split up into clearly demarcated subsections. A better solution may be to create separate pages as in Installing LinuxCNC -LinuxCNC -earlier, pre-namechange versions [please think of a better title] Install to CompactFlash has one instance of emc which I missed in January but otherwise is probably ok. LinuxCNC Pure Simulator is in a similar situation as Installing LinuxCNC. From an organizational point of
[Emc-users] MPG question
Hi all. I was wondering if it is possible to select the x,y,z axis from the keyboard just like jogging using the keyboard instead of a seperate switch for axis selection when using the MPG. I do not want to use a pendant and am running out of room on the panel of my control. What I was hopinng for was to jog with the direction buttons till I got close then hit the I key and use the MPG for the final touch off. Thanks Terry -- Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
Re: [Emc-users] the state of the Wiki
for section 2 Getting Started. I have not yet gotten too far with CAD/CAM to generate gcode, but I have a suggestion to run up the flagpole to see if anyone salutes. I suggest we select 2 CAD/CAM solutions to include on the CD, with special support in the wiki. One would allow complex things to be done (with it's steep learning curve), and one would be simple and easy, so as to have a short learning curve. I (selfishly) suggest we use blender for the complicated one (since I have a project that will require multiple parts to be attached having only axes in common). I have used GSimple to make some parts, but I recently found that LibreOffice Draw allows me to draw to scale. I have printed out a drill guide for center punching the location of holes in an orderly manner on a wooden project and the printout was practically to scale. Though I haven't tried it, Draw claims to be able to export to Scaled Vector Graphics (.SVG), and in the wiki the CAM plugin for blender is supposed to work off of the .SVG file. PyCAM is supposed to work with .SVG, so we might only need to cover instructions on using one CAM solution for both the easy and the hard. These two CAD/CAM solutions would get special emphasis on the wiki to get people up and running quicker, and these wiki pages would also be included on the CD. I know the CD is already nearly full, but I suspect we could make room for these, and if not, we could remaster it as a DVD with these tools and their necessary tutorials. Perhaps if a DVD is required, we could include video tutorials to further help out. On 04/27/2012 01:26 PM, Kent A. Reed wrote: Section 2. Hardware Requirements needs work to bring it up to current technology, both in terms of LinuxCNC and in terms of platforms. Since the following subsection LinuxCNC Supported Hardware also uses the word Hardware but in the sense of interfaces, I think it would be useful to choose the title Computer Requirements instead. LinuxCNC Supported Hardware is probably as good as it gets given the flux in the marketplace. Latency Test is a conundrum for me. I can't figure whether it would be better to sort it on brandname or on date of the system. Right now the table seems a mixture of top posting, bottom posting, and alphabetical posting. Still, I wouldn't want to throw the baby out with the bathwater. Why not have a few pages with the data sorted different ways, and links at the top of the pages so each points to each of the others, and the back link of all 3 of 4 pointing back to the wiki main page? -- Live Security Virtual Conference Exclusive live event will cover all the ways today's security and threat landscape has changed and how IT managers can respond. Discussions will include endpoint security, mobile security and the latest in malware threats. http://www.accelacomm.com/jaw/sfrnl04242012/114/50122263/ ___ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
