The GearN is either GND or not connected. I don't have control over those states (it's a motorcycle gearbox sensor). When the pin is not connected I reach 7.5V on the MCP-A0 point (it's a MCP23017 GPIO expander pin). Way more than I want to. I would like it to be in a low state when that happens.
Just wanted to ask how can I go about it?
Is this solution better? My reasoning: current flows constantly (that part worries me a bit) so the MCP23017 sees high state on it's pin (the GearN is in unconnected state). When GearN connects to GND current will flow directly to it and whole 12V will drop on R1 which will make MCP23017 read low state.
Is it sound? Is there any better way to do this? I don't feel comfortable having 6 lines (that's how many gears there are) constantly draw current (even though it can be minimal).