GPIO_MAX_PIN does not match datasheet? #58
Description
The tutorial here is for Raspberry Pi 4 which comes with BCM2711, and there are clearly 58 GPIO lines in the datasheet (Section 5.1). It is not clear where the number 53 comes from. Maybe it is from datasheet for BCM2835 used in older models?
Likely this does not matter for the tutorial, but it should be fixed if incorrect. More generally, the tutorial could use more comments to help people understand what the code is doing and where those magic numbers come from. (I happen to have a tiny little bit of knowledge of embedded programming to be able to look up things myself, probably not for most people who are reading the tutorial.)