Quadrature decoder
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From: GregS on 1 Jun 2010 14:53 In article <khka065j6tthlvak56n4c9pfchpkn83k0t(a)4ax.com>, Jim Thompson <To-Email-Use-The-Envelope-Icon(a)On-My-Web-Site.com> wrote: >On Tue, 01 Jun 2010 16:52:32 GMT, zekfrivo(a)zekfrivolous.com (GregS) >wrote: > >>Been searching all morning for one, and did find one by LSI/ LS7184. >> >>I have been looking at a drawing of one from the mid 70's, drawn up by >>a coworker who is long gone. >>using 74121;'s and 7400. >> >>I got a sample request, but I think i can do this myself quickly. I got > stepper motors >>and controllers requiring step and direction input. >>Good thing I have this diagram because I can't find others. >>Must be some other stuff around ?? >> >>I don't need indexing or counters. >>I also see optical encoders that have the outputs I need for the controllers. >>But I need something fast. >> >>greg > >Work statement too vague :-) > >What _exactly_ are you looking for? A _detector_ that produces a >pulse train _and_ direction? > > I also found this. All I would need is a separate toggle switch to choose direction, but not so cool...... <Spehro Pefhany <speffS...(a)interlogDOTyou.knowwhat> <wrote: > > If you only care about speed and not direction, one edge on one channel m= ay be sufficient. greg
From: Jim Thompson on 1 Jun 2010 15:08 On Tue, 01 Jun 2010 18:46:05 GMT, zekfrivo(a)zekfrivolous.com (GregS) wrote: >In article <khka065j6tthlvak56n4c9pfchpkn83k0t(a)4ax.com>, Jim Thompson <To-Email-Use-The-Envelope-Icon(a)On-My-Web-Site.com> wrote: >>On Tue, 01 Jun 2010 16:52:32 GMT, zekfrivo(a)zekfrivolous.com (GregS) >>wrote: >> >>>Been searching all morning for one, and did find one by LSI/ LS7184. >>> >>>I have been looking at a drawing of one from the mid 70's, drawn up by >>>a coworker who is long gone. >>>using 74121;'s and 7400. >>> >>>I got a sample request, but I think i can do this myself quickly. I got >> stepper motors >>>and controllers requiring step and direction input. >>>Good thing I have this diagram because I can't find others. >>>Must be some other stuff around ?? >>> >>>I don't need indexing or counters. >>>I also see optical encoders that have the outputs I need for the controllers. >>>But I need something fast. >>> >>>greg >> >>Work statement too vague :-) >> >>What _exactly_ are you looking for? A _detector_ that produces a >>pulse train _and_ direction? >> >> ...Jim Thompson > > >Right, pulse and direction. > >greg Like this... http://www.fpga4fun.com/QuadratureDecoder.html ?? I've seen self-clocking versions.... found this... http://archive.electronicdesign.com/files/29/21422/fig_02.gif But I've seen it done with a dual-D, but it escapes me right now :-0 ...Jim Thompson -- | James E.Thompson, CTO | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona 85048 Skype: Contacts Only | | | Voice:(480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at http://www.analog-innovations.com | 1962 | The only thing bipartisan in this country is hypocrisy
From: GregS on 1 Jun 2010 15:14 In article <hu3ksm$f87$3(a)usenet01.srv.cis.pitt.edu>, zekfrivo(a)zekfrivolous.com (GregS) wrote: >In article <khka065j6tthlvak56n4c9pfchpkn83k0t(a)4ax.com>, Jim Thompson > <To-Email-Use-The-Envelope-Icon(a)On-My-Web-Site.com> wrote: >>On Tue, 01 Jun 2010 16:52:32 GMT, zekfrivo(a)zekfrivolous.com (GregS) >>wrote: >> >>>Been searching all morning for one, and did find one by LSI/ LS7184. >>> >>>I have been looking at a drawing of one from the mid 70's, drawn up by >>>a coworker who is long gone. >>>using 74121;'s and 7400. >>> >>>I got a sample request, but I think i can do this myself quickly. I got >> stepper motors >>>and controllers requiring step and direction input. >>>Good thing I have this diagram because I can't find others. >>>Must be some other stuff around ?? >>> >>>I don't need indexing or counters. >>>I also see optical encoders that have the outputs I need for the controllers. >>>But I need something fast. >>> >>>greg >> >>Work statement too vague :-) >> >>What _exactly_ are you looking for? A _detector_ that produces a >>pulse train _and_ direction? Its been a long project. i tried to get an existing controller to work with my steppers. For a Z axis motion. I thought i needed more power so I used two audio amps to act as buffers from the stepper output. That did not help much. i didn't figure out why the motors did not like the drive output. So now I am wiring a separate Z axis system, which is a lot simpler than using the existing system. The movement is by knobs, and the speed will not be over 500 Hz. I also did not want to drive two steppers in sync, but thats what I was given. I could have also ordered an opto knob with step and direction outputs but its a time thing right now. greg
From: Jim Thompson on 1 Jun 2010 15:19 On Tue, 01 Jun 2010 19:14:04 GMT, zekfrivo(a)zekfrivolous.com (GregS) wrote: >In article <hu3ksm$f87$3(a)usenet01.srv.cis.pitt.edu>, zekfrivo(a)zekfrivolous.com (GregS) wrote: >>In article <khka065j6tthlvak56n4c9pfchpkn83k0t(a)4ax.com>, Jim Thompson >> <To-Email-Use-The-Envelope-Icon(a)On-My-Web-Site.com> wrote: >>>On Tue, 01 Jun 2010 16:52:32 GMT, zekfrivo(a)zekfrivolous.com (GregS) >>>wrote: >>> >>>>Been searching all morning for one, and did find one by LSI/ LS7184. >>>> >>>>I have been looking at a drawing of one from the mid 70's, drawn up by >>>>a coworker who is long gone. >>>>using 74121;'s and 7400. >>>> >>>>I got a sample request, but I think i can do this myself quickly. I got >>> stepper motors >>>>and controllers requiring step and direction input. >>>>Good thing I have this diagram because I can't find others. >>>>Must be some other stuff around ?? >>>> >>>>I don't need indexing or counters. >>>>I also see optical encoders that have the outputs I need for the controllers. >>>>But I need something fast. >>>> >>>>greg >>> >>>Work statement too vague :-) >>> >>>What _exactly_ are you looking for? A _detector_ that produces a >>>pulse train _and_ direction? > >Its been a long project. i tried to get an existing controller to work >with my steppers. For a Z axis motion. I thought i needed more power >so I used two audio amps to act as buffers from the stepper >output. That did not help much. i didn't figure out why the motors >did not like the drive output. So now I am wiring a separate Z axis >system, which is a lot simpler than using the existing system. >The movement is by knobs, and the speed will not >be over 500 Hz. I also did not want to drive two steppers >in sync, but thats what I was given. I could have also >ordered an opto knob with step and direction outputs but its >a time thing right now. > >greg If one phase clocks a D-flop which has as "D" the other phase, you get a direction signal. Pulses is pulses is pulses ;-) Maybe XOR the two phase for fun ?:-) ...Jim Thompson -- | James E.Thompson, CTO | mens | | Analog Innovations, Inc. | et | | Analog/Mixed-Signal ASIC's and Discrete Systems | manus | | Phoenix, Arizona 85048 Skype: Contacts Only | | | Voice:(480)460-2350 Fax: Available upon request | Brass Rat | | E-mail Icon at http://www.analog-innovations.com | 1962 | The only thing bipartisan in this country is hypocrisy
From: GregS on 1 Jun 2010 16:14
In article <fcma06psnvbk4oag04qsjdjt2sppd8ogqj(a)4ax.com>, Jim Thompson <To-Email-Use-The-Envelope-Icon(a)On-My-Web-Site.com> wrote: >On Tue, 01 Jun 2010 18:46:05 GMT, zekfrivo(a)zekfrivolous.com (GregS) >wrote: > >>In article <khka065j6tthlvak56n4c9pfchpkn83k0t(a)4ax.com>, Jim Thompson > <To-Email-Use-The-Envelope-Icon(a)On-My-Web-Site.com> wrote: >>>On Tue, 01 Jun 2010 16:52:32 GMT, zekfrivo(a)zekfrivolous.com (GregS) >>>wrote: >>> >>>>Been searching all morning for one, and did find one by LSI/ LS7184. >>>> >>>>I have been looking at a drawing of one from the mid 70's, drawn up by >>>>a coworker who is long gone. >>>>using 74121;'s and 7400. >>>> >>>>I got a sample request, but I think i can do this myself quickly. I got >>> stepper motors >>>>and controllers requiring step and direction input. >>>>Good thing I have this diagram because I can't find others. >>>>Must be some other stuff around ?? >>>> >>>>I don't need indexing or counters. >>>>I also see optical encoders that have the outputs I need for the > controllers. >>>>But I need something fast. >>>> >>>>greg >>> >>>Work statement too vague :-) >>> >>>What _exactly_ are you looking for? A _detector_ that produces a >>>pulse train _and_ direction? >>> >>> ...Jim Thompson >> >> >>Right, pulse and direction. >> >>greg > > >Like this... > >http://www.fpga4fun.com/QuadratureDecoder.html ?? Missed the diagrams, I was looking at earlier today. >I've seen self-clocking versions.... found this... > >http://archive.electronicdesign.com/files/29/21422/fig_02.gif > >But I've seen it done with a dual-D, but it escapes me right now :-0 > > ...Jim Thompson My first thought, simple, and perhaps even better, was to use just a toggle switch. I thought about using a VCO that would speed up the longer you hold the toggle up or down. You go up, and you go down. Not as precise though as in focusing a microscope. greg |