There are some references to the existence of Schmitt trigger inputs on the Raspberry Pi. There seems to poor and conflicting information on this point. There is https://www.scribd.com/doc/101830961/GPIO-Pads-Control2 but nothing in https://www.raspberrypi.org/app/uploads/2012/02/BCM2835-ARM-Peripherals.pdf. I saw another reference that seemed to use different addresses. Even the scribd article is short on specifics. It makes reference to a document "BCM2835 full data sheet" however the information listed does not appear in my copy of the data sheet. Perhaps there is another version somewhere that I can access? I not that there are not enough bits in the address range given to set power level and hysteresis for all pins. Am I missing something? This leaves a number of questions:
Is hysteresis available on all input pins?
Is it defaulted?
How do I set hysteresis on or off for a particular pin?
Is hysteresis and power level set individually on each pin or by banks of pins?
Should I rely on the Schmitt trigger behaviour in my board design, or is it likely to change in future without notice?