IR signal to external GPIO pin?

Hypothetically let’s say I was to take a walk in my neighborhood with my wife and my flipper and I notice that I left the TV on in the house and wanted to turn it off. I get my flipper out and hit the power button on the IR app but really isn’t bright enough from the street and through the window to reach the TV.
So I could try to attach a higher power emitter, maybe focused in a flashlight body to try to reach in the window to the TV.
I would need access to the internal signal that drives the internal LEDs. I just got my flipper last night and I am new to the whole thing. I looked at the schematics and see the GPIO for the IR_TX is not shared with an external pin. I looked at the source code but at first glance I didn’t see where it was assigning the GPIO in the software.
Where should I look? Can I make a separate IR app to use the alternate pin or ideally both at once?

Is there an easier way to solve this important problem?

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So I found the answer is to simply enable INFRARED_TX_DEBUG (set to 1) in furi_hal_infrared.c and the ir signal DMA will be sent to GPIO_PIN_7. I haven’t made an external emitter yet but I verified the signal looks good.

More later…

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Ever get any further on this? I have been trying to find more documentation on dives into GPIO for projects and this is another project I was going to dive into.

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MrFixit
Have a look here.

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I haven’t gone back yet. I was thinking when I do I would decouple it from the GPIO which needs a special build and disables the built in IR to using a repeater circuit. I have some Vishay IR receivers I would use instead of the GPIO and then stick the receiver in front of the flipper ir.

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Looks like I never followed up. tldr I got it working, not as awesome as I expected, needs more investigation.

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That is a hilarious and well documented build! There is a guy working on a similar project using the Flipper but for his local emergency services. IR can control some traffic lights but the units are extremely expensive. He is messing with ways to create a low cost alternative.

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I haven’t tried it on traffic lights yet but I have seen how it can be done. The IR flashlight is super cheap and throws a nice beam it seems like a good way to make something small and cheap. And of course it could be done with an arduino for a lot cheaper than a flipper.

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I think he said the Auduino wasn’t stable enough for the timing.

Found finally a 940nm Infrared Laser module @ <5mw on AliExpress, stay tuned it’s basically a laser pointer :ghost:

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Good luck! report back with results

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