I have a two questions: I want to know definitely exact answer - which digital pins (from 2 to 13) can I use:
1) - for power my simple circuit, for example - thermosensor ?
I want set this pin to HIGH and I expect that I'll get 3.3 volt and it power my thermosensor etc, then I set pin to LOW and power should stop.
2) - for using in SoftSerial mode or for 1-wire - In my project I'm already using some pins for SoftSerial (3 and 5) and for 1-wire bus (6 and
During my tests I figured out that only pin number 7 works as I expected - it provides 3 volts in HIGH state and 0 volts on LOW state. I uses it for power my thermosensors.
So I decided to test all pins and check voltage in OUTPUT mode.
I have simple code to check it:
I start Anarduino with this code for every pin from 2 to 13 and check voltage with multimeter.
Here are the values that I received:
As far I understand, only pins 6, 7 and 8 can be used for powering.
pin 5 provides 0.165v in sleep mode so it seems it will consume some power in sleep mode. not good.
pin 9 - it is onboard LED - also consumes power in sleep mode.
pins 2, 3, 4, 10, 11, 13 - have strange behavior and I can't use it for powering, but maybe some of these pins can be used for 1-wire or SoftSerial? For example I already using pin3 for SoftSerial RX.
But I'm not sure if I can use pins 9 - 13 - I have some doubts - seems they uses for SPI bus for connecting HopeRF LoRa module and if I choose some of that pins for powering my other circuit (mosfet key in my case) I think it lead to some issues with radio communication.
pin 12 also consumes in sleep mode.
This message was edited 1 time. Last update was at 12/03/2017 06:52:29