Using AUX pins as relays for CHDK

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?

You need to be a member of diydrones to add comments!

Join diydrones

Email me when people reply –

Replies

            • Thanks Reuben.

            • Hi Reuben,

              I hope that I can get several cables also as agreed :)

              Many thanks.

              Waladi

            • Family first. Thanks for checking in Reuben.
            • Thanks Reuben.

              Sorry to hear about the illness in your family.

              Bill

        • Wiki Ninja

          Hi Bill

          I've added this cable to the end of the CHDK wiki page here. I figure no point reproducing your user guide in a dedicated page ... and this is the first place people looking for a chdk solution on the wiki will go.

          OK by you?


          Cheers

          Hamsih

          • OK by me.

            Thanks Hamsih,

            Bill

        • I have tested the cable with a 5 volt UBEC and with 4 Afro ESC's with 0.5A linear BEC's. It works both ways. The UBEC gave me 5.33 volts on the AUX OUT rails, the linear BEC's gave me 5.03 volts on the AUX OUT rails.

          I had the UBEC pluged into AUX OUT 6.

  • 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?

This reply was deleted.

Activity

DIY Robocars via Twitter
RT @knightsautoteam: Hi @diyrobocars, we are Orlando's first Autonomous racing club and would love your support. We are hosting our first K…
Friday
DIY Robocars via Twitter
RT @Heavy02011: #VirtualRaceLeague: @DIYRobocars Race #14 - #ParkingLotNerds join us January 15th for #AutonomousRacing #RoboRace ⁦@DAVGtec…
Jan 16
DIY Robocars via Twitter
RT @chr1sa: And after that came our races, 50 in all. This battle between these two Russians was the best we've ever seen -- incredible fig…
Jan 16
DIY Robocars via Twitter
RT @chr1sa: Before our @DIYRobocars virtual race this weekend, we had a presentation from the team that won the Indy Autonomous Challenge i…
Jan 16
DIY Drones via Twitter
Dec 12, 2021
DIY Robocars via Twitter
Dec 12, 2021
DIY Robocars via Twitter
RT @chr1sa: Just a week to go before our next @DIYRobocars race at @circuitlaunch, complete with famous Brazilian BBQ. It's free, fun for k…
Dec 4, 2021
DIY Robocars via Twitter
How to use the new @donkey_car graphical UI to edit driving data for better training https://www.youtube.com/watch?v=J5-zHNeNebQ
Nov 28, 2021
DIY Robocars via Twitter
RT @SmallpixelCar: Wrote a program to find the light positions at @circuitlaunch. Here is the hypothesis of the light locations updating ba…
Nov 26, 2021
DIY Robocars via Twitter
RT @SmallpixelCar: Broke my @HokuyoUsa Lidar today. Luckily the non-cone localization, based on @a1k0n LightSLAM idea, works. It will help…
Nov 25, 2021
DIY Robocars via Twitter
@gclue_akira CC @NVIDIAEmbedded
Nov 23, 2021
DIY Robocars via Twitter
RT @luxonis: OAK-D PoE Autonomous Vehicle (Courtesy of zonyl in our Discord: https://discord.gg/EPsZHkg9Nx) https://t.co/PNDewvJdrb
Nov 23, 2021
DIY Robocars via Twitter
RT @f1tenth: It is getting dark and rainy on the F1TENTH racetrack in the @LGSVLSimulator. Testing out the new flood lights for the racetra…
Nov 23, 2021
DIY Robocars via Twitter
RT @JoeSpeeds: Live Now! Alex of @IndyAChallenge winning @TU_Muenchen team talking about their racing strategy and open source @OpenRobotic…
Nov 20, 2021
DIY Robocars via Twitter
RT @DAVGtech: Live NOW! Alexander Wischnewski of Indy Autonomous Challenge winning TUM team talking racing @diyrobocars @Heavy02011 @Ottawa…
Nov 20, 2021
DIY Robocars via Twitter
Incredible training performance with Donkeycar https://www.youtube.com/watch?v=9yy7ASttw04
Nov 9, 2021
More…