I have my button working great on a Pi 2 but not so much on a Pi 3. It powers down after about 5 seconds. As if pin 8 never comes up.
I poked around the site and saw a config.txt:
dtoverlay=gpio-poweroff,gpiopin=14,active_low="y"
But I'm not seeing any difference. I'm sure it's something really stupid that I'm over looking.
Any help would be super appreciated.
Could be lots of things causing it, and the simplest way to rule out most of them is to use a different GPIO pin instead of TX. If you change that 14 in the config.txt line to another GPIO that is available, and attach to that pin, there is a good chance that'll get you up and running.
I also tried pin 7 (GPIO 4) since it doesn't do double duty. (Trying to eliminate possibilities.) Also put a meter on both pins (7 and 8) and they are indeed coming up. I'm really at a loss. It works fine on a Pi 2 so this is really confusing me.
Does the pin stay at 3.3v the whole time?
When I first plug in the Pi 3, it starts at 3.11v then goes to 3.29.
The Pi 2 starts at 3.15v and goes to 3.32.
This is a super cheap meter and I'm guessing those numbers are close enough?
But yes, the pin on both Pis stays 3.3v.
Yeah anything over 2.5v is enough to keep it on. I'm a little baffled. Is this the same board you used on the Pi 2, or did you get two of them and this is the second one?
Same board. I do have another though. Would you like me to wire it up and try it?
Nope. Was just making sure it wasn't maybe being caused by a defective on/off board.
Ok one last thing to try. Disconnect the wire that goes between TX and the Pi 3, then connect a wire between TX and +5v out. This will keep the TX pin high and rule out the board being the cause. It won't know to power off when the Pi shuts down, but it will at least give us some info. You HAVE to disconnect the TX pin from the GPIO or you'll put 5v straight to the GPIO and bad things will happen.
