Getting an esc to do reverse from a microcontroler
 

HI


i'm trying to use a microcontroler (arduino) to control an ESC (the Dynamite tazer 15T)


i am giving it a PWM signal sweeping from 1 to 255 (when i hook up a servo it does a 180 back and forth) but i only seem to be getting forward
can anyone tell me what signal i should send it to get it to go reverse?? :confused:

any suggestions welcome

Kind regards

Wouter

Did you go through the ESC calibration-programming procedure? Also there may be a delay going into reverse to allow for braking and reduce abuse on the transmission and such.

I tried to last night, hooked up a pot to do so, but couldn't get it to work it does stay still for about 50% of the travel on the pot


i looked at the manuel for this esc and it mentions a programing button, but i dont see a buton annywhere , just an off-on switch and 2 leds, onbe red and one green, the red one had a icn of a shield next to it.

You might be looking at the wrong manual. The shield icon next to the red LED is on the 15T WP (WaterProof) version. The WP version has no calibration button.

Here is the manual for the 15T WP:

http://www.horizonhobby.com/pdf/DYN4925WP_Manual.pdf

The manual has absolutely no instructions for calibration! However, the 12T WP manual does, so you might try that:

http://www.horizonhobby.com/pdf/DYN4927WP_Manual.pdf

If I'm remembering correctly, isn't Neutral Throttle actually 50% duty cycle, forward is 51-100% and reverse is 49-0%? If your ESC is auto-calibrating (whatever duty cycle it sees on boot = neutral) this could be your issue.

No, the usual control range is from a positive-going pulse of about 0.9 to 2 milliseconds length. (The repetition rate is usually in the range of 7 to 20 milliseconds, but that doesn't determine servo or throttle position.) The so-called neutral point is different for different manufacturers and radios. It's usually around 1.2 to 1.5 milliseconds.

That's for old-school equipment, not the latest, proprietary "high-rate" stuff.

+1 Pretty much what I have seen including some variance on neutral. Many of the newer transmitters have a shorter period (aka frame rate on some radios) that requires digital or at least modern servos. Helps increase responsiveness and reduce latency.

Here is a typical graphical representation of the traditional signal (of course in practice it won't be this square):

http://www.ermicro.com/blog/wp-conte...2/servo_01.jpg

Aha, that's right. PWM, not PFM. Whoops. :)

DYN4925WP Control
 

I see that you were working on this.
With mine, I can not get it to do reverse after doing forward movement.
I've tried many different versions of the code following the forward movement. I had similar code work in the past and lost it.


Can you help me?
CODE: (with attempts commented out)

steeringPin.write(Left);
delay(1000);

//throttlePin.write(Stop);
// delay(5000);
throttlePin.writeMicroseconds(2000);
throttlePin.write(RVS);
//throttlePin.writeMicroseconds(2000);
throttlePin.write(Stop);
delay(2500);

throttlePin.write(RVS);
delay(150);
throttlePin.writeMicroseconds(0);

steeringPin.write(Strait);
delay(1000);