BS2 and servo

shmow

Hello all wise ones,
I'm have a Parallax continuous rotation servo running for a little game I've created (controlled by a BS2).
The only problem is the servo pulses when I power up my application.
Is there a way to prevent the servo from moving/pulsing when I power up my system?
Regards,
Shmow (less than wise)

Mike Green

There may not be a way to prevent this sort of movement, but you could try using a pulldown resistor, maybe a 4.7K or 10K resistor from the servo control line to ground. If the "twitch" is because of the way the servo does its initialization, there may not be a fix. If the "twitch" is because of the servo control line seeing a noise pulse and treating it as a movement, the pulldown resistor may help. Some servos from a different manufacturer or a different line from the same manufacturer may behave differently on power up.

shmow

Thanks Mike.
Just so I am sure of the connection you recommend - I connect this resistor from the BS2's control pin to ground in parallel with the servo? Did I get that right?
Regards,
Shmow

SRLM

You could dedicate another I/O pin and hook it up to a transistor, with the transistor sitting on one of the lines of the servo. Then, you BS2 could turn the transistor on. This would only work for the second situation Mike posed.