Hi, 2010/1/22 mattschinkel <[email protected]>: >> The problem, as I understand, might be when an interrupt occurs within a >> pulse, which seems to interfere with servo accuracy. > > I don't see this as an issue. > > If there is a interrupt during one pulse, the servo would seem (to the > user) to ignore that pulse since there will be many correct pulses > surrounding it. The servo cannot move that fast. > If there are many interrupts during many pulses, the servo would get > confused and possibly vibrate, but I don't think it will move way out > of position. Hopefully the user would not interupt it for an extended > period of time. extended period being 1sec (enouf time for the servo > to actually move some distance)
You obviously haven't tried it. If there is no load at the servo (e.g., when it is used to aim a sharp sensor), you can hear each irregular pulse. It moves slightly off and then corrects again. But when there is load on the servo, it moves away more (and takes more time to correct). 40 ms is enough for a servo to loose torque. 10 us will move the servo about 2 degrees. And in one second, a standard servo turns 260 degrees! I did numerous implementations of servo control and the reason I did not get to writin a lib yet is because it is pretty time-consuming to do it right. And IMHO it is not worthy to jallib to release a clumsy lib. But maybe my standards are too high and adds this library value to jallib, even if it does work properly when interrupts are used... > On Jan 22, 1:46 pm, Sebastien Lelong <[email protected]> > As far as I'm concerned, I have not much problem with PIC being dedicated to > moving servos, without being able to do other things. I see this as part of > a servo controller board (even shield, for jaluino), with a dedicated PIC on > it. It is not about a board dedicated to move servo's. It is about a board dedicated to moving *one* servo. And what is the value of board that can controle a servo, but has (hardly) any ability to receive information on the desired setpoint of this library? IMO a proper library should enable an application (servo controller) that support multiple servo's and communication (i2c, serial) at the same time. Joep -- You received this message because you are subscribed to the Google Groups "jallib" group. To post to this group, send email to [email protected]. To unsubscribe from this group, send email to [email protected]. For more options, visit this group at http://groups.google.com/group/jallib?hl=en.
