ON-OFF shim with OLED display

Support
1

I have received the ON-OFF shim and installed it succesfully. I do have a Adafruit OLED display (128-64) that I use to display system stats. Its IC2 address cannot be changed (as far as I know). It seems that it conflicts with the ON-OFF shim.
The Pi starts up but almost immediately shuts down. Any idea if there is a workaround or solution to make them work together ?
Thank you everyone for their time and eventual help.

PS: I’ve read all posts I found but if there is one that already addresses this and I’ve missed it, I would appreciate a link.

2

Can you specify which OLED you are using? There is one pure I2C/SPI that should be compatible, but the OLED-bonnet uses BCM17 causing conflicts with the on-off shim.

3

Hello and thank you for your reply. I am not using the bonnet,just a normal display. I’ve got it on pins 1(3.3v),2(SCA),3(SCL) and 5(GND).
No other logic on it. It gets identified on 0x3c address.
It is a generic display,not bought from Adafruit,but works with their libraries.

4

The hardware is not the problem: the onoff-shim does not use I2C. Please read the section ‘Parasitic Shutdowns’ in the repo of the shutdown script GitHub - pimoroni/clean-shutdown: Python daemon to watch a GPIO pin and trigger a clean shutdown.

5

I’ve looked at that link. It seems that somehow the GND connection of my OLED triggers the shutdown when the power supply is connected to the shim USB connection.
If I have the power on the Raspberry pi everything works but I loose the ability to start the Pi after a shutdown from the shim. Shutdown works,but not restart.

Just trying to further troubleshoot, I’ve disabled the startup script.Same thing happens when the power supply is connected to shim. Almost instant shutdown.
Moving the GND pin makes no difference.

I suppose I need to find another solution to have the OLED working and shutdown/restart capability. I was hoping that this shim will do that.

6

This is all very strange. The shim definitely can do what you want. Maybe you could post your config.txt? Do you have any other software running during startup that uses GPIOs?

Have you tried the on-off shim on a freshly installed PiOS? What kind of Pi are you using? Do you have stable power-supply?

7

I’ve figured it out. Some of the example scripts provided by Adafruit have a reset pin statement and I was using one like that. I have used a different one and everything works now.
Thank you bablokb for staying with this and asking the right questions so I can think of alternatives. I appreciate it.

The shim works now,the OLED stats script as well and now I can relax.

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