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Servo Control Problem

I know this looks common but mine is alittle unique. I have the PICAXE-08. Not M just 08. Which means i don't have a servo command. I tried seaking help and cwignell helped me as much as he could (Thanks a lot cwignell). But the servo just ends up spinning all the way to the left and jitters. I've tried his to example programs and PWM but the all end up the same

here's one:


low 1

    pulsout 1, 155

    pause 19 ‘ pause 19 ms

    goto main ‘ loop back to start 

They all dont work. I connected the red one to V. Brown to ground. and orange to signal(output 1). BUT i still get the all the way to the left treatment. I have a micro servo. PLEASE HELP. i need this to finish my trashcan project. This is the only thing holding me back.


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low 1 is there because the pulseout function goes low high low or high low high depending on the original state of the pin.

Low 1 is to ensure we see a high going pulse

Why is there a low 1 in there?
I assume its to make sure the pin is low before the pulse command is used.

Hey Tofu,

 I assume you don't have access to a CRO, a month or so back there was some posts about using the mic in ports on the PC with some software as a CRO, track down the post and I would look at the output with that.

The fact that the Servo jitters makes me think the wiring is ok.

 Oh one thing, what clock are you running? the timing in the above is only right for a 4MHz clock.

I have no idea how to check my clock. Nothing is working. I even tried looking at a magizine with an ardiuno program and try to translate it to PICAXE and it still just jitters. :( nothing is working.

what board are you using, what XLTAL or Resonator is one the board?

 You best bet is still to look at the out put to using a CRO.



OK, this seems basic, but it is always best to start by verifying "layer 1" as we say in the IT world. Check and double-check all your physical connections.

  • Is the servo signal pin wired correctly to your output pin 1?
  • Are all of your wires in good condition?

Next, the Picaxe manual mentions in the section on the pulsout command:

  • "This command automatically configures the pin as an output, but fo rreliable operation on 8 pin PICAXE you shold ensure this pin is an output before using the command."

Finally, have you tested other values for the duration in the pulsout command to see the effect it has?  This might not solve your problem, but try values between 125 and 175 and see if there is any difference in the effect.

Good luck.