Python GPIO Library for the Rock64 (R64.GPIO)

[edupv]

Internal SoC PullUps are usually between 20K to 100K.

So, using a external PullDown to put it low is like creating a voltage divider with the internal pullup, therefore with a external 20K, you get a voltage that is neither a LOW or a HIGH, explaining why you get interrupts triggered repeatedly.

If you use a external 1K as a pulldown instead, you will see that will be close to 0V ...

Thanks for your reply.

By calculation, the internal pull-up resistor is around 60K, it is normal.

As I expected the pin was pull-down internally and I had prepared a switch with 5K resistor to pull it up, so when I found the pin was pull-up, I was a little confused - I wanted to pull it down and use the switch to pull it up to trigger the interrupt.