On Tue, 13 Oct 2009, Dave wrote: > Date: Tue, 13 Oct 2009 17:06:56 -0400 > From: Dave <e...@dc9.tzo.com> > Reply-To: "Enhanced Machine Controller (EMC)" > <emc-users@lists.sourceforge.net> > To: "Enhanced Machine Controller (EMC)" <emc-users@lists.sourceforge.net> > Subject: [Emc-users] Mesa THC > > Hi Peter, > > I heard something about a Mesa THC board. Can you fill us in on that? > > Thanks, > > Dave
Yes, our THCAD, kind of done as a lark... Its just a simple isolated (2500V) Voltage to Frequency converter (V-F) for A-D use with either a hardware encoder counter (1 MHz full scale) or parallel port counting (various divisions of the 1 MHz FS rate) as the readout. Voltage is read as velocity. It has about 12 bits of resolution so better than .1V resolution at 300V full scale. It does have a bipolar option for general purpose use. There are 2 assembly option models, one with a base range of 0 to 10V (for external HV divider = RF start types or others with included dividers) and one with a base range of 0 to 300 V for direct connection to press start torches. 10V model has 100K input impedance 300V has 3M input impedance. Due to the nifty Analog Devices isolator+power chip, there is less than 2 pf between analog and digital sides. Since its only the isolated A-D part of the THC, EMC must handle all the smarts (but thats the EMC way) It has differential outputs for noise immunity (but outputs can be used single ended if desired for parallel port counting etc) John Thorton has a proto of this card and has done some work on a THC component that uses it. Heres a picture: http://www.mesanet.com/graphics/analog/thcadcolo.png Peter Wallace Mesa Electronics (\__/) (='.'=) This is Bunny. Copy and paste bunny into your (")_(") signature to help him gain world domination. ------------------------------------------------------------------------------ Come build with us! The BlackBerry(R) Developer Conference in SF, CA is the only developer event you need to attend this year. Jumpstart your developing skills, take BlackBerry mobile applications to market and stay ahead of the curve. Join us from November 9 - 12, 2009. Register now! http://p.sf.net/sfu/devconference _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
