Help me with what? With the fact that the pin is sometimes low, thus it is not reliable?
It's not sometimes low. All buttons work by either connecting or disconnecting the ground signal from an input, no buttons ever drive signals high.
If it's sometimes low like you say then you we don't even need to ground it, just boot up with the other buttons pushed.
On the switch side, pin 9 is always ground. Pin 10 has a 10kΩ to ground, and is driven to 1.8v when powered on.
Last edited by smf,