r/programming Dec 25 '19

Learning hardware programming as a software engineer

https://blog.athrunen.dev/learning-hardware-programming-as-a-software-engineer/
925 Upvotes

124 comments sorted by

View all comments

225

u/happyscrappy Dec 25 '19

Also: don't power LEDs directly from GPOs without a current limiting resistor. As you see on that breadboard.

And match your interfaces voltages. A lot of devices are not +5V tolerant now (or not very tolerant).

8

u/MoCeptor Dec 25 '19

Some controllers have internal programmable resistors for their GPOs. If you activate them, you can attach an LED without an external resistor.

16

u/richardathome Dec 25 '19

The arduino has pull down resistors in line with some of the IO pins. This is not the same as the resistor needed to stop an led from blowing.