This is my first circuit ever (!) and so I'm hoping that I'm just making an easy-to-spot rookie mistake. I am trying to power an Arduino Due with a 9V battery and then have the Due in turn power a red LED. No blinking. No sketchpad/C program flashed to the chip. Just straight up electricity:
When I connect the battery, several things happen:
- There is a green power LED on the Due that lights up; and
- Right next to it is an orange LED (on the Due itself) that blinks every few seconds (not sure what this LED is or what the blinking means, but providing that detail for good measure); and
- The red LED on the breadboarrd does not light up
This is a 2V/15mA LED, and as you can see I'm powering it from the 5V power jack on the Due. So a 220 ohm resistor should be perfect for it (
R = (Vs - V) / I = (5V-2V) / .015A ~= 220 ohms).
So, for the first time ever, I busted out my multimeter, set it to the voltage setting, and started testing the circuit. First I tested
GND on the Due (that is, the connection between the battery and the Due), and the multimeter lit up and hovered (correctly) around 5V. So far so good. Next I tested the power and ground connections on the breadboard power rails (indicated in green above). Again, the multimeter reported a roughly 5V power supply. Then I tested the connection from the power rail to the row (purple in pic above) feeding power to the resistor, and to my surprise, the multimeter reports no power at those two purple locations.
My understanding was that the power rail will power the entire column its connected to (in my case, the left-most column), and then any rows connecting to a power rail/column will also be powered. So I'm not understanding why there's voltage on my power rail/column, but not on the wire connecting my power rail to the resistor. Any ideas?
Here is my corrected circuit per initial feedback. Please note this is still not working, but I think I'm getting close: