Hi,
is it possible for Analog CH1 (no pull-up) to sense when a wire goes to ground?
Or do I have to make a trick with a relay and send a 12v?
Thanks
Please, never send 12v. These are 0-5v inputs, 12v would damage it.
Use a 2k to 10k resistor (value doesn't matter a lot, anything in there can work great) between the input and 5v and you're making your own pull-up. That's the best way. No need to get as complicated as a relay.
With the resistor in there as the pull-up, it will be up around 4-5v on the input when floating. If you ground the input, it will go to 0v, so you can set up a trigger for that action.
Quote from: jrussell on April 20, 2017, 02:03:22 PM
Please, never send 12v. These are 0-5v inputs, 12v would damage it.
Use a 2k to 10k resistor (value doesn't matter a lot, anything in there can work great) between the input and 5v and you're making your own pull-up. That's the best way. No need to get as complicated as a relay.
With the resistor in there as the pull-up, it will be up around 4-5v on the input when floating. If you ground the input, it will go to 0v, so you can set up a trigger for that action.
Thanks Russell, I'll use an external pull-up.
Anyway I forgot to say I read on this ecu paper that its CH1 is the only one that can get 12v...
Of course this also depends on what is before the 0V wire, since it may never get to 0 any more with the pull up ;)