I'd like to make a 4x4 pressure ( force resistance) sensor grid to use with an arduino. But 16 sensors sure need a lot of pins. During my research on this topic I stumbled upon a couple of suggestions. An example I've seen at least 100 times is the one which generates a 4x4 LED-grid. But in this example, there is no sensordata to be read.
So, backed up by the factories manual on how to hook the sensor up and on how the 4x4 LED-grid tutorial suggested I created my own idea on how to wire the whole thing with one arduino.
My thoughts on that: Keep D1 to D4 defined as OUTPUT HIGH. Set D5 to D8 alternatly as ground. Gather analog information through A2 to A5 of the current selected row. Save data and look at next row.
My question now, before ordering all the components: Does that sound realistic from an electrical point of view?
So the first answer got me thinking, and here is my new circuit plan:
Didn't I break the paralellity of the resistive sensors because I'm not measuring the resistance at the pins 5-8, instead I measure values at the analog pins 2 to 5. So now, if D5 is set to gound, the upper row of the sensors is powered and sensing data, which is gathered by analog pins 2 to 5. And then grounded in digital pin 5.