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Futaba Controller Servo issues Picaxe

I am trying to use my Futaba Radio Controller, intercept the pulse and then pass it through a servo.
I guess that I could use a relay but I would like to process the signal.

Here is a basic bit of code:

do
   pulsin 1,1,b0
   debug b0
   pulsout 2, b0
   pause 20
loop

this would seem to me that it would basicaly pass the signal from ch1 to ch2 but the servo is rather jumpy(servo moves back and forth).

I read similar post but resistors did not seem to help. it might be the controler.

Any help or experience would be greatly appreciated.

CodeEsan

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Chris,

 

Thanks for taking a look at the post. Actually when I first started on this project; I read your article. So it’s interesting that you stopped by to take a look here.

 

The variance that I am experiencing will not be seen nor measured by your project because you are adjusting a speed control with a motor. If you hook up to a say channel 2 on your receiver and then attach a servo to it you will see a small maybe 1step variance; kind of like a clicking of the servo. I believe that this is because the RC Controller is sending + or – 1 bit ie 153 = ( 154 or 152) .

 

I am working on a way to average the signal which should help.

 

pulsin 1,1,b0
b1 = (b1 + b0 ) /2

pulsout 2, b1
b1 = b0

pause 20

 

syntax maybe wrong but you get the picture.

 

Once again. Very nice to meet you and great work on your project.

 

If you would like get a hold of me via e-mail and I’ll show you what I’m working on. I don’t want to blog about it until it’s done. But I think that you would be interested in the project.

 

Thanks,

 

Cody

ps nice plymoth.. we have a few on the ranch.

http://letsmakerobots.com/node/2920

This is all I know. Mine worked when spitting out a number then used to adjust a PWM signal (as shown in the link above) and later, as a pulsout to the servo. 

You might want to remove the debug...

 

if you set w0 to a constant value say 150 and then pulsout in the same loop with out reading pulsin; everything is fine.

I have actually been thinking of buying an Oscilloscope in order to look at the actuall input from the controller.

 I have however debugged the data as it comes in picaxe and it is not jumpy.... or from what I can see at debug speed.

 CodeEsan

In effect i have the same problem and i try to understand why!! I bought an axe200 module with a 28X2 microcontroller, the code is similar:

 

main:

    pulsin C.0, 1, w0

    w0=w0-140

    pulsout B.4, w0

 goto main

 

the pwm signal in input has 48 Hz of frequency (from Rx).. in exit the frequency go down at 11 Hz!! ..with a little vibration.. if i try to make the identical function but by servopos command.. the frequency of output signal is ok but the vibration of the servo is enormous!! Somebody have some ideas??