How much current is needed in the 12 volt supply? I'm guessing less than 100 ma.
If you have 24 volts DC available then you can drop it down to 12 volts a few different ways but the simplest might be an LM7812 linear regulator. The LM7812 is nearly bomb proof. These cost under $2 Look at figure 9 on the datasheet and note the values of the caps are not critical at all. https://www.mouser.com/datasheet/2/149/LM7812-461970.pdf <https://www.mouser.com/datasheet/2/149/LM7812-461970.pdf> On Mon, Mar 30, 2020 at 6:54 PM andrew beck <andrewbeck0...@gmail.com> wrote: > hey guys I was asking about connecting a 12v mpg encoder to my mesa 7i76 > card. last week. I have done some testing with a pc atx power supply and a > multimeter and it looks like at 12 v when measuring between the A channel > and ground(0V) the high value is 5.2 volts and low is zero(or close to it) > also there are some nice status leds that show what the channels on the mpg > are doing. > > when powering it with 5 volts the leds don't work and the high voltage is > 2.7 volts and the low is zero volts. I read the threshold in the mpg > inputs is 2.5 volts with 10 percent hysteresis so I need to pull at least > 2.8 volts. also I am thinking that might be a bit close and result is > unreliable operation. > > Is there anyway I can supply this with 12 volts from my board? I am > running the field voltage at 24volts. > > regards > > Andrew > > > On Tue, Mar 24, 2020 at 7:53 AM Peter C. Wallace <p...@mesanet.com> wrote: > > > On Tue, 24 Mar 2020, andrew beck wrote: > > > > > Date: Tue, 24 Mar 2020 07:34:01 +1300 > > > From: andrew beck <andrewbeck0...@gmail.com> > > > Reply-To: "Enhanced Machine Controller (EMC)" > > > <emc-users@lists.sourceforge.net> > > > To: "Enhanced Machine Controller (EMC)" < > emc-users@lists.sourceforge.net > > > > > > Subject: Re: [Emc-users] connecting up mpg > > > > > > Hey Peter. > > > > > > When I enable the mpg mode does that mean I will lose my whole config > or > > do > > > I just need to change something in the Hal file. > > > > YOU just change some settings in the hal file > > > > > > I'm thinking It sounds like the best thing is to setup all my io in > > > pnfconfig leaving the mpg inputs spare and then after that start hard > > > coding in Hal. > > > > Yes leave the 2 or 4 pins (for 1 or 2 MPGs) free if you want to use a MPG > > Note the enabling the MPG in the hal file will not cause you to lose the > > ability > > to use inputs 16..19 for normal digital input use > > > > > Do you know how much I can do in pnfconfig? > > > > > > > I dont think pncconf supports MPG setup, so this needs to be done by > > editing the > > HAL file > > > > > > > New Zealand is going in to total isolation for a month from tomorrow > > > because of covid 19 so I have some time for this lol :) > > > > > > Regards > > > > > > Andrew > > > > > > Regards > > > > > > Andrew > > > > > > On Mar 24, 2020 3:18 AM, "Peter C. Wallace" <p...@mesanet.com> wrote: > > > > > > On Mon, 23 Mar 2020, andrew beck wrote: > > > > > >> Date: Mon, 23 Mar 2020 17:32:56 +1300 > > >> From: andrew beck <andrewbeck0...@gmail.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] connecting up mpg > > > > > >> > > >> Hey guys. > > >> > > >> I have a 12 volt mpg > > >> > > >> I want to connect it to the 7i76 board. do you know if I can connect > it > > >> straight up. I think that the mesa boards only want 5 v and I am not > > sure > > >> how to connect up my 12 volt mpg > > >> > > >> > > > > > > https://drive.google.com/file/d/1uOF2y7KFSchXLhQ3s79GSB1x_WZieQ5l/view?usp=sharing > > >> > > >> I did a bunch of searches on the forum but couldn't get a definite > > answer. > > >> > > >> I tried to attach a photo but it bounced back. so here is a link > > >> > > >> regards > > > > > > > > > You can connect a 12V MPG to the 7I76 MPG inputs (field inputs 16..19), > > but > > > not > > > the high speed encoder input. Note that the input threshold for MPG > > inputs > > > is > > > 2.5V so the MPG output needs to swing close to ground for reliable > > operation > > > > > > > > > > > >> > > >> < > > > > > > https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail > > >> > > >> Virus-free. > > >> www.avast.com > > >> < > > > > > > https://www.avast.com/sig-email?utm_medium=email&utm_source=link&utm_campaign=sig-email&utm_content=webmail > > >> > > >> <#DAB4FAD8-2DD7-40BB-A1B8-4E2AA1F9FDF2> > > >> > > >> _______________________________________________ > > >> Emc-users mailing list > > >> Emc-users@lists.sourceforge.net > > >> https://lists.sourceforge.net/lists/listinfo/emc-users > > >> > > > > > > Peter Wallace > > > Mesa Electronics > > > > > > (\__/) > > > (='.'=) This is Bunny. Copy and paste bunny into your > > > (")_(") signature to help him gain world domination. > > > > > > > > > > > > > > > _______________________________________________ > > > Emc-users mailing list > > > Emc-users@lists.sourceforge.net > > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > > > > _______________________________________________ > > > Emc-users mailing list > > > Emc-users@lists.sourceforge.net > > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > > > > > Peter Wallace > > Mesa Electronics > > > > (\__/) > > (='.'=) This is Bunny. Copy and paste bunny into your > > (")_(") signature to help him gain world domination. > > > > > > > > _______________________________________________ > > Emc-users mailing list > > Emc-users@lists.sourceforge.net > > https://lists.sourceforge.net/lists/listinfo/emc-users > > > > _______________________________________________ > Emc-users mailing list > Emc-users@lists.sourceforge.net > https://lists.sourceforge.net/lists/listinfo/emc-users > -- Chris Albertson Redondo Beach, California _______________________________________________ Emc-users mailing list Emc-users@lists.sourceforge.net https://lists.sourceforge.net/lists/listinfo/emc-users
