Post by thread:optical rotary encoders with PICs : The final Word

Dear All, Thank you for all your help with this. I do have faith! Anyway, to sum up. I haven't been able to find optical encoders in the UK for less than 35 pounds. However, I am now using a Bourns mechanical quadrature encoder from Farnell which is relatively cheap at 3 pounds. Cirkit doesn't stock Bourns anymore. Thanks to some edge detection code, I am now Sorted! Anson Chuang

> Anyway, to sum up. I haven't been able to find optical encoders in the UK > for less than 35 pounds. However, I am now using a Bourns mechanical > quadrature encoder from Farnell which is relatively cheap at 3 pounds. > Cirkit doesn't stock Bourns anymore. > > Thanks to some edge detection code, I am now Sorted! > > Anson Chuang Hi, I'm following this discution and did anyone have ever used Step Motor as shaf encoder? I did a small test and it works very fine. Octavio ======================================================== Octavio Nogueira e-mail: spam_OUTnogueiraTakeThisOuTmandic.com.br homepage: www.geocities.com/SiliconValley/Pines/6902 voice/fax: +55 11 240-6474 "ProPic" The first Production PIC Programmer running in Windows and under US$ 20.00. ========================================================

How are they wired up? myke {Quote hidden}>> > Anyway, to sum up. I haven't been able to find optical encoders in the UK >> > for less than 35 pounds. However, I am now using a Bourns mechanical >> > quadrature encoder from Farnell which is relatively cheap at 3 pounds. >> > Cirkit doesn't stock Bourns anymore. >> > >> > Thanks to some edge detection code, I am now Sorted! >> > >> > Anson Chuang >> >> Hi, I'm following this discution and did anyone have ever used Step Motor >> as shaf encoder? I did a small test and it works very fine. >> >> Octavio >> ======================================================== > >Yes, they are very strong and relatively cheap. I use them to replace pots on >interactive exhibits, even the strongest most destructive child cant >seem to break them. >Paul Waterfield >Exhibit designer >Techniquest >Stuart Street >Cardiff CF1 6BW >UK >T +44 (0) 1222 475 475 >F +44 (0) 1222 482 517 > > "I don't do anything that anybody else in good physical condition and unlimited funds couldn't do" - Bruce Wayne

Greetings; I once tried to use stepper motors as shaft encoders. I just had comparators set so the hysteresis trip level was just enough to triger the threshold and latch it into binary ( with positive feedback ). The problem I was having was that you have got to turn the "pot" at least FOUR clicks before a direction can be realized. The reason being, unlike optically encoded predecessors a coil could go positive or negative DEPENDING on which DIRECTION you came from. If someone has come up with a way, though , of course I would love to hear it ;-> p.s You've got to at least try it, it's fun! Hamilton At 04:45 PM 1/24/97 EST, you wrote: >How are they wired up? > >myke >>> > Anyway, to sum up. I haven't been able to find optical encoders in the UK {Quote hidden}>>> > for less than 35 pounds. However, I am now using a Bourns mechanical >>> > quadrature encoder from Farnell which is relatively cheap at 3 pounds. >>> > Cirkit doesn't stock Bourns anymore. >>> > >>> > Thanks to some edge detection code, I am now Sorted! >>> > >>> > Anson Chuang >>> >>> Hi, I'm following this discution and did anyone have ever used Step Motor >>> as shaf encoder? I did a small test and it works very fine. >>> >>> Octavio >>> ======================================================== >> >>Yes, they are very strong and relatively cheap. I use them to replace pots on >>interactive exhibits, even the strongest most destructive child cant >>seem to break them. >>Paul Waterfield |_ _ _ _ | )(_|( | ) @ s l i p . n e t http://www.slip.net/~ham http://www.mesaboogie.com

> Greetings; > > I once tried to use stepper motors as shaft encoders. I just had > comparators set so the hysteresis trip level was just enough to triger the > threshold and latch it into binary ( with positive feedback ). The problem > I was having was that you have got to turn the "pot" at least FOUR clicks > before a direction can be realized. The reason being, unlike optically > encoded predecessors a coil could go positive or negative DEPENDING on > which DIRECTION you came from. If someone has come up with a way, though , > of course I would love to hear it ;-> > p.s You've got to at least try it, it's fun! > > Hamilton This is similar to how I did it. Connect up two of the phases to comparitors, remove the negative portion and feed into the PIC Paul Waterfield Exhibit designer Techniquest Stuart Street Cardiff CF1 6BW UK T +44 (0) 1222 475 475 F +44 (0) 1222 482 517