nogardvfx
Posts: 14
Joined: Mon Nov 02, 2020 1:53 pm

Re: Status LEDs to GPIO header

Thu Nov 26, 2020 7:48 pm

ok good to know! Sketchy internet info led me to the one I have.
Order this: https://www.mikroe.com/max3232-board

DarkElvenAngel
Posts: 1397
Joined: Tue Mar 20, 2018 9:53 pm

Re: Status LEDs to GPIO header

Thu Nov 26, 2020 8:04 pm

rpdom wrote:
Thu Nov 26, 2020 6:18 pm
The MAX323 chip will put 5V on the Pi's GPIOs which will damage the Pi. You should use a MAX3232 instead which will work at the correct 3.3V levels.
Good catch!

Now to fix your led problem it's really should be easy you don't need anything complex. Have you tried to just hook an LEDs up to GPIO 14 and 15? This should work for a quick test if you want to be safe you can use a transistor or a logic ic.

Well to give you a simple setup that you can replicate I would use a 2n2222 only because I have a ton of these.

Here is a simple setup http://www.learningaboutelectronics.com ... ircuit.php please note the values of the resistors a 1kΩ and 330Ω those are the correct values to use. (No I didn't calculate them I just know that they work) in the diagram from the link the resistors is 3kΩ this should be 1kΩ, the GPIO replaces the switch and 1.5v supply.

Does that help?

nogardvfx
Posts: 14
Joined: Mon Nov 02, 2020 1:53 pm

Re: Status LEDs to GPIO header

Thu Nov 26, 2020 11:45 pm

Very helpful, but maybe not dumbed down enough for me. Sorry. I have put together a pic that shows what I *think* it would be wired up as. The only thing I am not sure is which wires go to where on the NPN 2N2222. To be honest, I don't even know if this is correct in any way.
Attachments
wiring2.jpg
wiring2.jpg (123.85 KiB) Viewed 185 times

DarkElvenAngel
Posts: 1397
Joined: Tue Mar 20, 2018 9:53 pm

Re: Status LEDs to GPIO header

Thu Nov 26, 2020 11:51 pm

nogardvfx wrote:
Thu Nov 26, 2020 11:45 pm
Very helpful, but maybe not dumbed down enough for me. Sorry. I have put together a pic that shows what I *think* it would be wired up as. The only thing I am not sure is which wires go to where on the NPN 2N2222. To be honest, I don't even know if this is correct in any way.
It looks right to me.

nogardvfx
Posts: 14
Joined: Mon Nov 02, 2020 1:53 pm

Re: Status LEDs to GPIO header

Fri Nov 27, 2020 12:15 am

Ok I have ordered the 2N2222 transistors and then I will give this a go. Thank you for the help. Will post results when it is done.

nogardvfx
Posts: 14
Joined: Mon Nov 02, 2020 1:53 pm

Re: Status LEDs to GPIO header

Tue Dec 01, 2020 7:15 pm

Got the parts last night and hooked it all up this morning and it all works! Thank for your help and patience.

Cheers!

DarkElvenAngel
Posts: 1397
Joined: Tue Mar 20, 2018 9:53 pm

Re: Status LEDs to GPIO header

Tue Dec 01, 2020 9:19 pm

nogardvfx wrote:
Tue Dec 01, 2020 7:15 pm
Got the parts last night and hooked it all up this morning and it all works! Thank for your help and patience.

Cheers!
No worries, I'm happy it worked it out for you!

Enjoy

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