Tackling Graceful Shutdowns on the GBZ
- Camble
- Posts: 885
- Joined: Thu May 05, 2016 2:31 am
- Location: Scotland
- Has thanked: 269 times
- Been thanked: 488 times
Re: Tackling Graceful Shutdowns on the GBZ
@alien0matic How do you have the power hooked up for your screen?
- alien0matic
- Posts: 102
- Joined: Wed Jun 08, 2016 7:20 am
- Has thanked: 15 times
- Been thanked: 23 times
Re: Tackling Graceful Shutdowns on the GBZ
I made a small breakout board that everything gets its power from.
The problem seems to be that the GPIO is never pulled down because the transistor isn't "opening".
The problem seems to be that the GPIO is never pulled down because the transistor isn't "opening".
- Camble
- Posts: 885
- Joined: Thu May 05, 2016 2:31 am
- Location: Scotland
- Has thanked: 269 times
- Been thanked: 488 times
Re: Tackling Graceful Shutdowns on the GBZ
You can use a simple voltage divider to reduce the LBO voltage to a safe level and wire that straight to a GPIO pin.
- alien0matic
- Posts: 102
- Joined: Wed Jun 08, 2016 7:20 am
- Has thanked: 15 times
- Been thanked: 23 times
Re: Tackling Graceful Shutdowns on the GBZ
But the solution from this thread should work, too, shouldn't it? I have everything set up for this, would be good to get it working.
- Camble
- Posts: 885
- Joined: Thu May 05, 2016 2:31 am
- Location: Scotland
- Has thanked: 269 times
- Been thanked: 488 times
Re: Tackling Graceful Shutdowns on the GBZ
@alien0matic Yes. I'm just saying, there's a low battery output on the PowerBoost.
- alien0matic
- Posts: 102
- Joined: Wed Jun 08, 2016 7:20 am
- Has thanked: 15 times
- Been thanked: 23 times
Re: Tackling Graceful Shutdowns on the GBZ
Ok, I measured the voltage on the base pin of the transistor to be 0.58V when the LED is fully lit. Reading this https://www.sparkfun.com/datasheets/Com ... 2N3904.pdf the transistor will switch on 0.65V. Which means the voltage is too low. Should I just add another resistor with less Ohm? I already tried shorting the resistor, but that causes an instant shutdown.
- Camble
- Posts: 885
- Joined: Thu May 05, 2016 2:31 am
- Location: Scotland
- Has thanked: 269 times
- Been thanked: 488 times
Re: Tackling Graceful Shutdowns on the GBZ
@alien0matic I don't know, I don't use that solution for low battery
Re: Tackling Graceful Shutdowns on the GBZ
Do you think you could design a circuit that uses a momentary power button instead of a throw switch?
I know you could just hook up a button to GPIO and configure it to shutdown the pi, but with the same button, could you power the pi back on again?
I know you could just hook up a button to GPIO and configure it to shutdown the pi, but with the same button, could you power the pi back on again?
Who is online
Users browsing this forum: No registered users and 1 guest