OnOff SHIM - Questions regarding GPIO allocation and wiring


#1

Hey there,

I make it short, I have 2 questions (as in my project this would be necessary):

1.) I want to solder a short cable with micro USB plug to the Shim to connect it to the micro USB connector instead of the 5 V Pin of the pinout. Is something wrong with that?

2.) As GPIO 17 is used from another addon in my project (and I think it won’t be so easy to change that), I would connect the board to an other GPIO Pin. Were to find the PIN assignment in the scripts, can it be changed easily?

So my wiring (bold, were i differ from the pinout on https://pinout.xyz/pinout/onoff_shim#):

Pin 1 OnOff SHIM --> Pin 1 RasPi (3,3 V)
Pin 2 OnOff SHIM --> Cable Connected to the Micro USB Plug (5 V)
Pin 6 OnOff SHIM --> Cable Connected to the Micro USB Plug (GROUND)
Pin 7 OnOff SHIM --> Pin 7 RasPi (BCM 4, Shutdown)
Pin 9 OnOff SHIM --> necessary, as Ground is connected through Pin 6?
Pin 11 OnOff SHIM --> Pin 22 RasPi (BCM 25 instead of BCM 17)

Thank you very much in advance!

nosi


#2

Hey there,

no one out there who can help me?


#3

Hi nosi,

Sorry for the lack of reply. Yes, it’s possible and will work like that, but if the Pi current draw is higher than the charge current, the battery will discharge even if you keep charging it.


#4

Hi Matt,
thank you for your answer.

Just to recap if I got it right:

  • If I do the wireing like mentioned above (connect the 5 V Output of the SHIM with the Micro-USB +5 V Input of the Pi), the Power is not fully cut, if the OnOffShimm shuts the Pi down?
  • But if I connect it to the Pins, the board does so (cut the power)?

Or have I completly mistaken the sense of the OnOffSHIM? The only reason I want to use it, is to cut the power and reduce the current used in stand by. Shutting the Pi down and waking it up have I already realised with a GPIO Button…that was not the reason for what I bought the SHIM…

Many thanks in advance.

nosi