I recently purchased an elegoo uno to try and get started in the Arduino world, and everything has been working very well, but I noticed today while building a set of 10 led's blinking in pattern that even though they had the same resistor value to each, some were a lot duller than others. I traced back the wires and it was only those connected to pins 4-7, and those from 8-13 were much brighter. I tried swapping the led's about to see if it was just a coincdence, but it was just with those pins. I even tried removing the resistors completely from those connected to the lower pins, but even with no resistor they were duller than those with a 220 ohm on the higher pins. If anyone knows what's wrong and if there's a way to solve this it'd be much appreciated.
Ah okay, have found someone with a similar issue on another forum, and it can be solved by adding:
void setup() {
pinMode(13, OUTPUT);
for (int pinindex = 0; pinindex < 14; pinindex++) {
pinMode(pinindex, OUTPUT); // set pins 0 to 13 as outputs
}
to the code, setting all pins to outputs.
Hope this helps anyone with the same issue
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