Derek Holzer wrote:
This makes sense. I used some FSRs with a hacked joystick HID device and got into some trouble there as well. FSRs have zero resistance when no force is applied, so essentially you are short circuiting the 5v directly to ground when you plug them in without any force applied. I would definitely try a resistor in series with each FSR, that's how I did it with the HID joystick, which also crashed (the joystick did not function) when the FSR was plugged in without any resistance.
FSR have a very _high_ resistance with no force. The resistance goes down when you apply pressure. The circuit needs to look like this:
5V | 10k | +------analog in | FSR | Ground
This will give a number that goes down as force is applied. If you want the number to increase, switch the 10k and FSR.
Looking at the (considerably more expensive than a 10k resistor) phidget voltage divider I see that the resistance is a multi-turn 1Meg potentiometer. If it is set to zero ohms then pressing a sensor will short out the power supply. Also by convention the red wire is 5V, the black wire is ground and the white is the analog signal.
Martin