-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 On 1/11/2013 8:25 PM, Ed Nisley wrote: > What I need... > > Guidance around my blind spots! > > F'r instance, I'm sure I've missed a hardware gotcha. Are there > more practical ways to drive five stepper axes, get a bunch of > digital I/O, and read thermocouples? > > Although I'm generally a big fan of lashing up surplus parts in my > shop, I want to do this with reasonably standard hardware, so as to > simplify building the next one. It's coming out of my pocket, > however: the sky is *not* the budgetary limit.
I believe Mesa has some analog input cards that are supported by the hostmot2 driver, if not it probably wouldn't be too hard to add support. As you mentioned, the Arduino is one way to get some cheap I/O, and there are examples of integrating this with HAL already: http://axis.unpy.net/01198594294 "Tooting my own horn", a couple other ways to do this include: Directly interface an I2C ADC to a couple pins on the parallel port and talk I2C via a custom HAL module. I have done this and used the result to connect LinuxCNC via a parallel port to a standard RAMPS board. It worked well enough to print reasonably well, and would work a lot better with a more sophisticated thermal control algorithm (I was using a bang-bang thermostat, it wouldn't be too hard to work up a PID control with feed-forward coming from the extrusion rate). Details and code are in my github repo: https://github.com/cdsteinkuehler/LinuxCNC-RepRap ...and what I personally am working on for the 'future' of LinuxCNC control of 3D printers: Interface the BeagleBone to a 3D printer, running LinuxCNC on the ARM core, and using the 'Bone's integrated hardware (ADC, PWM, and high-speed PRU co-processors) to handle the low-level control. I'm currently working on this along with several others (see the developer list for LinuxCNC on ARM goodness), using the BeBoPr shield for the BeagleBone as a starting point for the hardware: http://circuitco.com/support/index.php?title=BeBoPr_Cape > I'll surely have a bunch more questions as I make progress over the > next few months (the M2 will likely take several months to arrive), > but I'd appreciate any advice in the interim. I design hardware for a living, and am *VERY* interested in seeing LinuxCNC controlling a 3D printer *WELL*, so holler if you have any questions. I am currently working on the hardware end of things, but there is a lot in the interface, control, and HAL configuration that could be done to help things along. The nice thing about LinuxCNC is if you can get a good solid working configuration on one platform (parallel port + Arduino, Mesa cards, BeagleBone or whatever), it should be pretty straight-forward to port to alternate hardware. - -- Charles Steinkuehler char...@steinkuehler.net -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.11 (MingW32) Comment: Using GnuPG with undefined - http://www.enigmail.net/ iEYEARECAAYFAlDw4yAACgkQLywbqEHdNFyVdwCeMtSuACDkkcIU4RmDnrfph7lM XJwAoIVvefdydJOKb5PDrgDRp3qBCiRE =bvk2 -----END PGP SIGNATURE----- ------------------------------------------------------------------------------ Master Visual Studio, SharePoint, SQL, ASP.NET, C# 2012, HTML5, CSS, MVC, Windows 8 Apps, JavaScript and much more. Keep your skills current with LearnDevNow - 3,200 step-by-step video tutorials by Microsoft MVPs and experts. SALE $99.99 this month only -- learn more at: http://p.sf.net/sfu/learnmore_122912 _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
