Are D13 and A7 on the arduino Nano connected?

Hi! I am working on a 5x5 matrix. I am testing out if i have connected everything right, and i came across this problem that I can't solve. If i turn on all the ground lines (D2-D6), and connect the lowest red row (A7) I can see that the highest blue row also lits up. Then if I connect the blue line (D13) the red row doesn't light up. The wires are very far apart. I've checked with a multimeter and the wires are completely isolated. Any idea why this is happening and how I could solve this?

Hi! I am working on a 5x5 matrix. I am testing out if i have connected everything right, and i came across this problem that I can't solve. If i turn on all the ground lines (D2-D6), and connect the lowest red row (A7) I can see that the highest blue row also lits up. Then if I connect the blue line (D13) the red row doesn't light up. The wires are very far apart. I've checked with a multimeter and the wires are completely isolated. Any idea why this is happening and how I could solve this?

Not sure what you are doing with A7, but A7 is an analog input only. Unlike A0 to A5, A6 and A7 have no digital function.

biggizmo:
found some thing about D13 might help you
https://forum.arduino.cc/index.php?topic=461765.0

You mean this answer regarding confusing the markings on the Nano board!

Sorry, but the OP needs to demonstrate how they have wired this matrix - schematic diagram and explanation of what red and blue LEDs are, preferably with a photo taken with perfect focus and detail in outside daylight, not in a dim room - in order for us to assist. :roll_eyes:

Duplicate topics moved and merged

Cross-posting is against the rules of the forum. The reason is that duplicate posts can waste the time of the people trying to help. Someone might spend 15 minutes (or more) writing a detailed answer on this topic, without knowing that someone else already did the same in the other topic.

Repeated cross-posting will result in a suspension from the forum.

In the future, please take some time to pick the forum board that best suits the topic of your question and then only post once to that forum board. This is basic forum etiquette, as explained in the sticky "How to use this forum - please read." post you will find at the top of every forum board. It contains a lot of other useful information. Please read it.

Thanks in advance for your cooperation.

UKHeliBob:
The reason is that duplicate posts can waste the time of the people trying to help. Someone might spend 15 minutes (or more) writing a detailed answer on this topic, without knowing that someone else already did the same in the other topic.

Precisely as demonstrated here by replies #2 and #3 to the originally separate postings. :roll_eyes: