Abstract: A system and method to automatically calibrate resistance-based sensors connected to a first joystick input on a computer game port adapter by affixing known resistances to a second joystick input on the game port adapter is disclosed. The corresponding software establishes a first relationship between the known resistances and corresponding adapter voltages (as represented by respective pulse counts). Based on this relationship, the software automatically calibrates the sensor attached to the game port adapter using a variable voltage signal (and corresponding variable pulse count) generated by the sensor due to the variations in the sensor resistance based on an environmental condition (e.g., temperature, humidity, etc.) being monitored by the sensor. The sensor's variable resistance value is calculated based on the sensor voltage input and the first relationship.