Wiring LEDs to an Teensy

[MMMaus]

Hi,

I have built my own keyboard and all keys work, I am actually typing this post on it, but I can't get the LEDs to work. I have an AVR Arduino Board AT90USB1286 U Disk TE502, which I got from ebay, and bought blue LEDs. After some research I have bought 150 Ohm resistors. I am pretty sure that I have not made an mistake with soldering the LEDs.

Today I tried again to get this working. I found this thread: keyboards-f2/wiring-up-scroll-key-leds- ... 11006.html
and followed flabbergast's advice: <pin on teensy> --- LED anode (+) - LED cathode (-) --- resistor --- ground
but nope, it still doesn't work.

Does anyone have an idea? Did I use the wrong resistors? Wrong Teensy board?

[Findecanor]

* Did you you have your build environment configured to compile for the AT90USB1286 (Tensy++ 2.0) and not for the ATmega32U4 (Teensy 2.0) ?
Most firmwares are made for the latter and the chips are mostly compatible but there are a few differences.
* Did you configure the pins on the ports correctly?

[MMMaus]

Yes, I am sure I used the right board and I soldered them to the right pins. I accidently used the wrong board once and the whole keyboard didn't work at all because of that.

[Mazian]

Pretty sure you have that backwards, definitely if it's running QMK and I expect so as well if it's TMK. +5V → LED → resistor → Teensy is how I have my QMK numpad wired - the target Teensy pin acts as a sink, not a source. LED and resistor can be in either order, whichever's easier to wire.

[MMMaus]

Pretty sure you have that backwards, definitely if it's running QMK and I expect so as well if it's TMK. +5V → LED → resistor → Teensy is how I have my QMK numpad wired - the target Teensy pin acts as a sink, not a source. LED and resistor can be in either order, whichever's easier to wire.

Thanks! That was the problem. Everything works now!