detect potentiometer change on output pin.

[rb8720]

Can anyone tell me how you would detect a change in the potentiometer in this circuit. Pins 2 and 3 are connected to tact switches that are connected to ground. 6 and 7 are connected to the wiper of the left and right pots. and 4 and 5 are not used. Pin 1 is connected to +3v and Pin 8 is connected to a transistor connected to the pot. What i don't understand is if you only have 1 pin connected to the pot and it is used for output how do you detect if the pot is turned? The pot is actually the trigger on a xbox controller. The chip is designed to make the contrller rapid fire when the trigger is pulled. Under normal operation when the trigger is pulld the middle leg is taken low which fires the trigger. so for the chip to make it rapid fire the out put pin ( pins 6 and 7 ) must toggle between High and low ( or tri state) to simulate the triggre being pulled and released rapidly. the buttons connected to pins 2 and 3 toggle the chip operation from doing nothing to rapidfire. So if pins 6 and 7 atre output and 2 and 3 are ot connected to the triggers. How does the chip detect when the triggers are pulled. Can you read adc and output on the same pin at the same time? Here is a very rough drawing of the circuit.

RB8720

[Ttelmah]

You can switch pins between being inputs, outputs, and ADC inputs, pretty quickly. As shown, there is no way to detect the setting of pot2. However, I'd guess that the real circuit has some differences. Possibly something as simple as an unconnected length of track connected to one end of the pot, routing close to something else. The understanding, will be in small details like this.

Best Wishes

[SherpaDoug]

The connection of Pot 1 and the transistor doesn't make any sense to me either. Something is wrong somewhere.
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[Humberto]

The quasi-circuit shown does not have any sense.
...Pin 1 should be +Vdd
...Pin 8 should be Gnd
...hence the transistor should be a P type...
...hence all is wrong.

Humberto