Introduction - If you have any usage issues, please Google them yourself
There are four external interrupt sources (EINT0, EINT2, EINT11, EINT19) in line Turi,
The initial potential of the high potential VDD_3V3. We can GPIO PIN, GPB6 and GBP7 located
Set at a low level so that when the button is pressed, the potential to generate a high potential to low potential transfer state,
As triggered the interrupt sources.
• the line number we know SW1 and SW5 have the same interrupt signal EINT0, so we will
Need to distinguish when the button is pressed, there is low potential generated SW1 or SW5, which
KEY SCAN s precisely the point.