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Unread 11-02-2005, 08:32
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Re: Making a 5k joystick work

Quote:
Originally Posted by jgannon
As I understand the OI and the analog inputs on the RC, they measure the voltage on signal pins with respect to +5 and ground...
That is true of the RC analog inputs. However, it is not how the joystick inputs on the OI work.

The OI measures the resistance between +5 and the joystick input pin, using an internal resistor to ground to complete the voltage divider. It is designed specifically for a 100k variable resistor. There is no ground connection to the other end of the joystick pot.

The "disconnected" detector merely notices that the sensed voltage is at ground. A 5k pot will result in that voltage being very near 5 volts, so it won't trigger that problem.