Hi.Got my red ATMEGA328 ArduPilot from the latest Sparkfun batch a couple of days ago, and I am having problems getting the servos working.First I tough the attiny45 was missing failsafe code, so I flashed v15 of the failsafe. No luck there, still no servo response. So I started scoping the in/out pins and I noticed that the servo control input pulses from the receiver are pulled down. Signals out from receiver is ok (3.5v), but the moment I connect them to Ardupilot inputs 1-4 they drop to 1v. CTRL input seems fine and has a 3.5v signal when connected and MUX and MODE status LED are triggered by remote. I have not looked at why the signal is pulled down yet and really don't feel like doing so either, since I bought the Ardupilot so I could start coding right away without designing the electronics first.
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Ha! Your right! I can't believe I didn't catch that! Not what you normally look for I guess. :)
But at least something that's quick and easy fix then. Thanks!
3.5v on the control signal is what you find in most receivers. Some Futaba receivers even go as low as 2.7v. It is power that is 5/6v.
And seeing how it's just a couple of pin headers I can't imagine how they can be soldered wrongly. I just measured to be sure and there are no shorts. As I mentioned, neither servo input or output is working. The only servo port working is CTRL. When I connect a receiver channel to input 1-4 the signal is pulled down to 1v p-p (puls timing is still fine). Output signals are about 0.5v with lots of noise. I can post some scope pictures if you want.
Looks like you created a short in the soldering. We've got a bunch of the new boards and they all work fine.
Just to confirm, your servos (connected to ArduPilot's OUT pins) aren't working in either RC or autonomous mode? If that's the case, it's almost certainly a soldering error or the connectors are plugged in backwards.
Hi John. If you have 3.5v out from the receiver, I think it might be too low for powering the ArduPilot board. It should receive something like 5v, or at least 4.7-4.8! Check out your battery pack to Rx. even servos run normally at 4.8V, if not at 6v to have faster response and more torque.
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But at least something that's quick and easy fix then. Thanks!
And seeing how it's just a couple of pin headers I can't imagine how they can be soldered wrongly. I just measured to be sure and there are no shorts. As I mentioned, neither servo input or output is working. The only servo port working is CTRL. When I connect a receiver channel to input 1-4 the signal is pulled down to 1v p-p (puls timing is still fine). Output signals are about 0.5v with lots of noise. I can post some scope pictures if you want.
Ardu.jpg
Just to confirm, your servos (connected to ArduPilot's OUT pins) aren't working in either RC or autonomous mode? If that's the case, it's almost certainly a soldering error or the connectors are plugged in backwards.