Shutdown function interferes with hack header/i2c?

Picade
1

I want to use i2c (for https://shop.pimoroni.com/products/rgb-encoder-breakout). If i plug the encoder breakout into the hack header, it immediately triggers a shutdown.

Can i redirect this, or do i have to disable the shutdown functionality with the DT overlay? Will that even work?

2

If your plugging it in while the Pi is powered up and running, you shouldn’t do that.
The basic shutdown dtoverlay dtoverlay=gpio-shutdown is disabled if i2c is enabled.
With i2c enabled you have to set the pin used for shutdown, like this,
dtoverlay=gpio-shutdown,gpio_pin=17,active_low=1,gpio_pull=up
If you do that you don’t want to use pin 3. If you do, stuff like what your experiencing will happen.

3

Switched the gpio-shutdown to 26, saved, shut down, removed power, hooked up 3v3/sda/scl/int/gnd from the encoder breakout to the hack header, pi won’t start up. Red button turns on, then directly off when i try to power it up. If i remove the header, pi will start as normal. Going to have to troubleshoot on a non-hatted pi.

Is there a way to pass the new shutdown pin thru the picade hat after switching the gpio_shutdown overlay? The pinout for the Picade hat says gpio17 is used by “power button”, and only gpio-26 is unused.

4

I have no idea what is going on? Adding an i2c device to the hack header shouldn’t effect the Picade Hats shutdown function. Not as far as I know anyway. And the shutdown function may not be done via that overlay?
Was there a shutdown dtoverlay entry there or did you add one? If you added one I would remove it.

5

I thought pin4 interference was causing the problem with the rotary encoder breakout, due to the pinout for the picadeX hat (https://pinout.xyz/pinout/picade_x_hat) showing gpio4 labelled as “shutdown” but having the same problem with the encoder on a base pi as well, so it’s most likely a problem with the encoder.

6

Ok, pin 4 being used for shutdown isn’t what I was expecting? I should have looked at the pinout before posting. Sorry about that. I goofed on that one.
Good pratice would be to use a different pin if i2c was ever going to be used.