By default (IIRC), pins 5 and 6. Short them together and the system shuts down. Do it again, and it reboots. All it takes is a single line in /boot/config.txt.Imperf3kt wrote: ↑Thu Jun 13, 2019 12:55 amI assume OP is looking for a way to leave the Pi in "standby" mode for convenient on / off via a button on their remote control much like how your TV functions.
You could probably just setup something that momentarily shorts the run pin to ground upon detecting a certain frequency.
Maybe a transistor and IR LED? Hit IR LED with beam from remote, transistor detects current and opens the gate.
Just an idea, I have no idea how practical it would be or if it would work as I think.
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It needs a little more than that but can easily be done with a microcontroller or another Pi. The main problem isn't so much powering-on as preventing a reset at an inopportune time.
I think I ought to point out that a TV that can be "turned on" or "turned off" with a remote, is never really "off". As in my point about, *something* has to be active for that trick to appear to work.
CEC is a separate electrical signal from the other HDMI signals. This allows a device to disable its high-speed HDMI circuitry in sleep mode, but be woken up by CEC. It is a single shared bus, which is directly connected between all HDMI ports on a device, so it can flow through a device which is completely powered off (not just asleep).
The bus is electrically identical to the AV.link protocol, but CEC adds a detailed higher-level message protocol.
The bus is an open-collector line, somewhat like I²C, passively pulled up to +3.3 V, and driven low to transmit a bit.
No, not without external hardware.
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HDMI Cable Pi Computer .--------------. _|_ | .-.__ | | | ========| |__| | | CEC Reset | `-' |___|----. o | | | | | `------|---|---' | | .------|---|---. | | `--------------' CEC Wake-Up Detector