Shop OBEX P1 Docs P2 Docs Learn Events
Problems w/ servos on Propeller BOE-Bot — Parallax Forums

Problems w/ servos on Propeller BOE-Bot

hyperritualhyperritual Posts: 11
edited 2013-01-20 16:50 in Robotics
Greetings,

I have an old BOE-Bot that worked fine with the BASIC Stamp BOE, and I just replaced that with the Propeller BOE. I cannot get the (standard Parallax continuous rotation) servos to work on the latter. I am using the code from http://learn.parallax.com/PropellerBoeBot. I have verified that when the power switch is in the third position (2) there is 5V between PWR and GND pins for P14 and P15. I have verified that the servos work fine by connecting them to the Arduino BOE-Bot shield; I am able to center and run the servos as expected using the code from http://learn.parallax.com/ShieldRobot. But when the servos are connected to the Prop BOE, I get weird stuff happening e.g.:
1. When both servos are connected, none of the code examples work at all (see 4).
2. If I disconnect either servo, I can get some response from the connected one, but it behaves strangely, e.g., when I run the centering program (http://learn.parallax.com/node/273), the servo spins until I adjust it but once it has stopped spinning it will not spin again no matter what position the potentiometer is in. If I reload the program, the servo begins spinning again according to the current pot position until I adjust the pot again, and then stops completely again. By reloading the program over and again, I can get the servo centered.
3. Once the servo is centered, running the program that should make it move in one direction and then the other (http://learn.parallax.com/node/274) only makes it move in one direction; after the first pause, it does not move anymore until I reload the program.
4. Using the program reloading technique I described in (2), I can get each servo centered and moving in one direction before it quits, but when I connect both servos, the two together will not respond to either program mentioned.

I thought I would check here for ideas about what the problem might be, before emailing Andy or opening a support ticket. I searched the forum but did not find anything that matched what I have been experiencing.

Thanks,
Joshua
Sign In or Register to comment.