Hi John, That would explain why I can not find the datashettes for the chips in the servo I opened up. Regards Luis Luis Moreira luis.moreira@jet.uk tel. 01235464615 JET PSU Department UKAEA Culham Division J20/1/55, Culham Science Centre Abingdon Oxfordshire OX14 3DB -----Original Message----- From: piclist-bounces@mit.edu [mailto:piclist-bounces@mit.edu] On Behalf Of John Ferrell Sent: 13 July 2005 18:55 To: Microcontroller discussion list - Public. Subject: Re: [OT] R/C servos control Send the correct value to the position and let the electronics handle speed & overshoot problems. BTW, the servo chips are not available to the public, just authorized service centers and the factory. John Ferrell http://DixieNC.US ----- Original Message ----- From: "David P Harris" To: "Microcontroller discussion list - Public." Sent: Wednesday, July 13, 2005 12:57 PM Subject: Re: [OT] R/C servos control > Robert Rolf wrote: > >> Luis Moreira wrote: >> >>> Hi Rolf, >>> What you are saying is that there is no braking as such, but if I forced >>> the servo to move before the next pulse the controller would try to get >>> it back to the original position. Is that correct? >> >> >> No. >> It only makes the correction with repeated pulses. >> The controller takes the difference between the internal monostable >> controlled by the pot, and the input pulse, and uses >> that difference (error) to drive the H bridge using simple logic. > > I hadn't realized this is how they worked... very elegant. So, if I want > to get to another position quickly, I could exaggerate the position to > maximize the error to increase the movement per pulse, and then sent the > correct position to zero in on it. This would have to take into account > the characteristics of the servo, but could give better performance. > David > > > -- > http://www.piclist.com PIC/SX FAQ & list archive > View/change your membership options at > http://mailman.mit.edu/mailman/listinfo/piclist -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist -- http://www.piclist.com PIC/SX FAQ & list archive View/change your membership options at http://mailman.mit.edu/mailman/listinfo/piclist