Re: [Paparazzi-devel] 5v pulse required for CHDK on Lisa/M2

[Marc Schwarzbach]

Hi Gerard,

since there is only very low current involved (measured) I connected the USB + 
line to 5V and the - line to an IO, using it as drain... Did this on a LPC 
based board. Not sure if I used a resistor, did that some time ago and now it´s 
deep inside the plane.

It has been working many flights triggering my CHDK camera now.
Probably not a "correct" solution and not sure if it works with the STM in the 
LISA.

Of course, I also had to reverse the logic in the dc_cam code...

If you find a solution, please post, anyway!

Cheers

Marc


-------- Original-Nachricht --------
> Datum: Thu, 1 Nov 2012 19:22:40 -0300
> Von: Gerard Toonstra <address@hidden>
> An: address@hidden
> Betreff: [Paparazzi-devel] 5v pulse required for CHDK on Lisa/M2

> Hi all,
> 
> I think I'm nearing the point where I can start some test flights with my
> setup.
> 
> I'd like to use a camera to take pictures. In my case that's a Canon with
> CHDK extensions.
> When the software detects 5V at the USB port, it triggers a picture to be
> taken.
> 
> I'm connecting this to one of the ADC's, but the voltage is 3.3v and not
> enough to trigger
> the camera. I've verified this using a 3.3v supply from an arduino. So I
> definitely need a higher
> voltage.
> 
> Is there any other pin I could use that does output 5v, which is
> configurable in the dc_cam module,
> or can this only be solved by inserting a level shifter?   If a level
> shifter is required, what
> are recommended components / boards?
> 
> Regards,
> 
> Gerard