Flow and LED deck combined?

Discussions and questions about the Crazyflie Nano Quadcopter
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liebs29
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Flow and LED deck combined?

Post by liebs29 » Tue Dec 19, 2017 10:04 pm

It seems like it might not be, but I cannot get heads or tails before I order. Is the flow deck and LED ring deck able to be used together?

tobias
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Re: Flow and LED deck combined?

Post by tobias » Wed Dec 20, 2017 8:03 am

Unfortunately that is not possible. It might be possible to drill a hole through the led-ring for the camera to see through or connecting a neopixel ring similar to what we once did on the CF-nano. However the light from the leds might fool the optical flow sensor when it is close to the ground though. Would be fun to test!

kristoffer
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Re: Flow and LED deck combined?

Post by kristoffer » Fri Dec 22, 2017 7:56 am

It is not possible out of the box, but if you are prepared to modify the LED-ring (and voiding any warranties and risk breaking it) it is. Take a look at the hack (https://www.hackster.io/krichardsson/li ... one-d050af) I wrote yesterday, it shows how it can be done.

droneguy
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Re: Flow and LED deck combined?

Post by droneguy » Fri Sep 14, 2018 6:53 pm

Hmm, that's very interesting! Great article!

Operationally, I have a question - the Flow deck uses the LeftExpansion7 (IO_2) pin and so does the LED Deck for the serial data for the WS2812B LEDs (labelled on the schematic as PWM_DOWN). How does that pin overloading work?

Images for reference...

Flow Deck:
Flow_Deck.JPG

LED Ring Deck:
LED_Deck.JPG

tobias
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Re: Flow and LED deck combined?

Post by tobias » Mon Sep 17, 2018 1:10 pm

In that hack I think it the front led signal line was just cut.

droneguy
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Re: Flow and LED deck combined?

Post by droneguy » Mon Sep 17, 2018 2:46 pm

Huh... then how does the firmware handle it?
When the drivers for the flow deck and ring deck are enabled, IO_2 is still overloaded in the firmware right?
That is, the ring deck will output a PWM on the line, and the flow deck driver will implement the RESET/MOTION logic?

droneguy
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Re: Flow and LED deck combined?

Post by droneguy » Tue Sep 18, 2018 2:52 pm

Nevermind.... I just saw that IO_2 is NOT used on the flow deck :P

Even though the schematic shows R4, R5 and R6 connected to IO_2, they are not populated on the boards.
Maybe update the schematic to reflect this?
Inkedflow_deck_400px-3_grande_LI.jpg
Inkedflow_deck_400px-3_grande_LI.jpg (205.13 KiB) Viewed 22 times

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