Subject:
|
r/c servos
|
Newsgroups:
|
lugnet.robotics
|
Date:
|
Fri, 20 Aug 1999 09:51:57 GMT
|
Original-From:
|
John Barnes <barnes@sensors.com/AntiSpam/>
|
Viewed:
|
667 times
|
| |
|
|
In response to the question about RC servos, I noted, while probing
the signals on the I/O ports with a scope, that the motor power settings
result in varying duty cycle square waves from 1:7 through 7:1 and finally
full on as the parameter value sweeps 0 -7.
Since RC servos use pulse width as the input, there is already potential
here. Does any one, with a deeper knowledge of the insides of the RCX code
know if the squarewave duty cycle is being controlled by software or a
hardware based PWM?
If it's s/w, then the rep. rate could be dramatically reduced and finer
timing resolution used to drive the servo position input.
thoughts?
JB
--
Did you check the web site first?: http://www.crynwr.com/lego-robotics
|
|
Message has 3 Replies:
 | | Re: r/c servos
|
| I love the idea of controlling an R/C servo with the RCX, but I don't think it is possible with only software. On the other hand, a relatively simple circuit could be made to convert a duty cycle to a R/C servo signal. Is anyone out there interested (...) (25 years ago, 20-Aug-99, to lugnet.robotics)
| | | Re: r/c servos
|
| (...) It is a software-based PWM. The topic of controlling a servo with the RCX has been discussed before. Generating the pulse stream for a servo would not be too difficult with the RCX, assuming you program the H8 directly using e.g. LegOS or (...) (25 years ago, 20-Aug-99, to lugnet.robotics)
| | | Re: r/c servos
|
| (...) If all you need to do is generate a pulse of a certain length, why can't you do something like this? Sleep(1); // synchronize with the centisecond timer Fwd(OUT_A, 7); Sleep(1); // 1/100 of a second Off(OUT_A); Sleep(2); // 2/100 of a second (...) (25 years ago, 20-Aug-99, to lugnet.robotics)
|
5 Messages in This Thread:
 
 
- Entire Thread on One Page:
- Nested:
All | Brief | Compact | Dots
Linear:
All | Brief | Compact
|
|
|
|
Active threads in Robotics
|
|
|
|
|
|
