basic servo help

drinkmaster

Hello,
I am trying to get a servo to work with a basic stamp. I seem to be having trouble.... I have tried 3 different servos. Two Parallex CR servo and one HITEC hs-625mg not CR servo. No matter what I do i can't seem to get anything to work. As soon as I load the code to the basic stamp the HITECH will flutter, or the parallex will just rotate and won't stop. It doesn't seem to matter what code I use or even what pin i attach the servo to, but i have attached what I am using below. To power the servos I am using a 6v power supply rated at 300ma. Not the same supply has basic stamp, Could someone please help, it seems like a simple task.

Servo_pin CON 0
start:
   PULSOUT Servo_pin, 750
   pause 20
GOTO start

NWCCTV

Not sure about the other Servos, but for the Parallax Servos 750 is stooped. Try 850 and or 650.

PJAllen

More details.

Which Stamp are you using?
Are you also using a BoE (or what)?
Do you have the negative lead of your 6V supply connected to Stamp Vss?

A continuous rotation servo will keep rotating and a standard servo will keep a position, given the same pulse width with each refresh (cycle).

ajward

Just a thought... have you centered your continuous servos? The "pulsout servo_pin, 750" command might not stop the servo if you haven't.

Amanda

erco

First, use a 6V battery pack instead of your tiny adapter. You DID connect your grounds together? Negative Stamp (ground, Vss) connects to your servo's negative voltage. Then try this and report back, servo on pin 0:

start:
for b0=1 to 255
PULSOUT 0, 650
pause 20
next
for b0=1 to 255
PULSOUT 0, 850
pause 20
next
GOTO start