Bypass power button

[CarlM]

Hi,
we want to use VIM as an unattended linux server.
That means in case of a short power failure the machine must
come back up alone, without sitting there waiting for someone to push
the power button.

How could that be done?
Connecting some pins of the 40-pin header?
Doing some soldering?

Thank’s for your reply

[mcahornsirup]

With a powerbank between the charger and the vim, you do not have to think about short outages : ) Maybe this could solve the problem as well. (I know, it does not answer your question ; )

[RDFTKV]

The Vim boots when power is applied. If the Vim is running and loses power, when power is restored, the Vim will boot.

[Gouwa]

Hi, CarIM:
Following solutions for your reference:
1) There are two ports can provide the power for VIM: VIN and USB-C, so you can provide the power with two separate power source. Check the Extra Power Input for Vim for details.

In this case: VIM power down only when both of the two power are dropped.

2) There is a power control signal to enable/disable the system power for VIM: PWR_EN, currently, PWR_EN will be 1 when the power AO_5V is applied, so as what RDFTKV mentioned above, the device will boot automate when the power is applied:

The PWR_EN is also available on 40-Pin GPIO, it means that you can design an external power circuit/module with the dropping detection:

• USB-C as the mainly power supply, and default as ON state.
• 4-Pin VIN as the secondary power supply, and default as OFF state.
• If the manly power drops down, the PWR_EN will be 0, in this case, the external power module will enable secondary power for the 4-Pin VIN by hardware
  
  

[CarlM]

Thank you RDFTKV and Gouwa for your replies, specially Gouwa for his
detailed explanation.

That has solved the question and I can go ahead and purchase some VIMs.

Thank’s again