I'm confused and a bit frustrated, would appreciate any help as I'm not sure how to proceed.

Setup: I have a pixhawk autopilot running Arduplane 2.77, using Mission Planner 1.2.95

I've been following this guide to get my CHDK enabled camera working with my pixhawk. I'm interested in getting the camera triggering based on distance traveled.

Obviously the guide was written with APM in mind, so it needs to be adapted a bit for pixhawk; specifically the setting for RELAY_PIN. I've kept the rest of the settings the same as in the tutorial.

Pixhawk has 6 AUX ports according to the quick start guide, I am assuming that the numbers above the pins correspond to the AUX port numbering. When you mouse over the RELAY_PIN parameter, it says that pin 54 corresponds to Pixhawk FMU AUX1.

Tried setting RELAY_PIN to 54, no joy. Did a bit more looking, discovered in the release notes for 2.77: 

"Improved relay code
The relay and servo set code has had a major overhaul, with up to 4 relays now supported for MAVLink control and much better support for the DO_SET_SERVO, DO_SET_RELAY, DO_REPEAT_SERVO and DO_REPEAT_RELAY MAVLink commands. Along with these changes is a new parameter BRD_PWM_COUNT which allows you to specify how many auxillary PWM outputs to enable, with the remaining outputs being available as digital relays. This allows you to re-assign some of the aux servo outputs on Pixhawk for use as relays, by setting the RELAY_PIN, RELAY_PIN2, RELAY_PIN3 and RELAY_PIN4 parameters. The pin numbers for these pins start at 50 for the first aux servo pin, and go to 55 on Pixhawk."

Additionally,I found this github issue about this same problem that states that the Pixhawk can't trigger CHDK because its relay pins operate at 3.3V instead of 5V.

So i suppose my specific questions are:

1) Is AUX1 pin 50 or 54?

2) Can anyone confirm that the relays, when working properly, won't be able to trigger CHDK?

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Hi Brenner,

Could I get you to contact us on our SkySight mail info@skysight.eu - then I will inform you about the posibilities for faster shipping..

Best regards

SkySight Team

Just checked our shipping partner... 4-5 days for shipping, and then depending on the speed of customs in Brazil.. Orders will first ship on 7th of April due to national Easter Holydays at the Danish post offices..

If you have any questions regarding the above, or specific to the use of MONO - don't hesitate to contact us..!

Best regards
SkySight Team

Sorry to inform, but the linked USB cable is also just a regular USB "B" cable - not a MultiPort cable..

Hi Plinio Augusto,

It depends if you already have a trigger solution, since you're not able to trigger a Sony MultiPort with the cable alone..
There is not much on the market for Sony's MultiPort eqiupped cameras - hence the reason we made a "plug&play" solution to help people out..

If you haven't already seen it - we just launched our webshop 5 days ago with our new product..


Best regards
SkySight Team

The connector you're looking for is like the one used on this "Remote Control with Multi Terminal Cable"

You could make a DIY solution with the cable from this remote, or a clone of it, but you would still need some kind of trigger that converts the R/C PWM signal to something that would trigger the camera..

Watch the video on our MONO product page to learn more about our "plug&play" solution for Sony MultiPort equipped cameras..

SkySight, i remind you that this is not a discussion only to promote your products but mainly devoted to "DIY".
limits your post about this, thanks.

I have Marco's circuit working on a breadboard. Now looking into testing it in flight. What is the best way to power the 5 v ubec? Is it ok to steal power from the main flight battery or is it better to use a secondary battery?

Has anyone heard from Reuben? I sent him $22 for a cable which he says was sent on Feb 4. Last time I heard from him was Feb 24 when he said he would send it again if I didn't have it in a week. That was 2 months ago. I haven't been able to reach him via email or PM. last time he posted here was Mar 14.

I know he's a legit guy, and a valued member of our community. I hope he's ok.

Has anyone else got their cable from him or been in contact?

I posted back on page 21 (March 13) that I got my cable from Reuben, but it didn't work. He said he had a new cable design and would send one of them when he got the parts. That's the last I heard from him. I have since purchased a cable from Tuffwing, although I haven't had a chance to check it out yet.



I wanted to make a cable based on Marco's design, but never had the time.

Hi. So I tested Marco's circuit in flight and it worked perfectly. Interestingly, I also tested the circuit without providing 5V to the Aux rail.... and it still triggered my camera!? I don't really understand why. I thought maybe the 3.3V from the PixHawhk was enough to trigger my particular camera model (Canon ELPH 110HS) but no.... I did a test with a simple USB cable and it did note trigger. Does anyone know what's happening? Where is this 5V coming from?

What is your esc type? Opto or the one that have bec?

The Tuffwing cable works perfectly.

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