2021-03-14, 12:15 AM
(2021-03-11, 07:33 PM)SARASTRO Wrote:The resistor does 2 things - first, like you said, provides a minimum current draw and secondly, it brings the voltage down quickly when power is cut so the shutdown signal is fast.(2021-02-25, 01:24 AM)Techstyle Wrote: That's Awesome - thanks for Sharing!I find the idea very interesting , and I want to test it using a EDLC capacitor instead of a second permanent supply line. (to avoid the additional wirings from de battery to the navpod)
with regard to Power, I found that I didn't trust other boat users to not turn the power off at the switches accidently so I added some simple electronics to my Pi to make the schematic below:
with this the switched power is connected to the breaker panel and the const 12V is connected to battery, if the switched voltage goes off it is sensed at pin 40 and a power down is started, once the Pi shuts down, the relay is turned off, disconnecting the constant 12V. the hardware costs less than $10 and looks like the below:
By connecting a momentary switch between pin 40 and ground, you can also start the shutdown process when pressed
I supuse that the resistance is placed to produce a minimum current drain from the 3,3v supply. Is this?. What is the value you use for that?
Thanks for your help
I believe it is a 1K resistor.
Please keep me updated with how you get on with the capacitor. It would be good to understand what peripherals you have connected.