Hall Effect: A Hall effect sensor is a transducer that varies its output voltage in response to a magnetic field. Hall effect sensors are used for proximity switching, positioning, speed detection, and current sensing applications. In its simplest form, the sensor operates as an analog transducer, directly returning a voltage.
Discussion: - What would you use this for? - what if we connect to 3v vs 5v? - no pulldown?
- can we get jitter in readings? - what happens if we move it back and forth very very fast? (e.g., mechanically?) swap pi: What if you get no output?
hardware heuristics: - if h/w read/write has to be volatile. - hardware bugs = nothing happens. look for stupid stuff first. e.g., put wires where you don’t have to count. hardware is not eternal like 0,1: use differential analysis to check if broken
- swap sensor. - swap pi --- if you don't have protection, can work initially, then fry. natural to partition project. don't for device. easy to misunderstand. have partner do too without talking hope to get non-correlated errors. - the pdf's can have errors! - just b/c it 'works' does not mean it does. this is very common with dangerous voltages --- just hasn't fried pin yet.