Controlling a DS1809 chip

I need to control a DS1809-010 digital potentiometer chip with a Nano. The chip has two control inputs. Up and down to control the swiping action of the pot in the chip. The inputs require a ground pulse to increment the swipe (either up or down). When the input is not being used it needs to be an open circuit like a switch or relay contact. It cannot be pulled up to 5 volts.

My question is what output function can I use to send a ground pulse and then return to an open circuit.

Thanks!!

Link to spec sheet for chip. https://datasheets.maximintegrated.com/en/ds/DS1809.pdf

When the input is not being used it needs to be an open circuit like a switch or relay contact. It cannot be pulled up to 5 volts.

The datasheet says something different. The both control inputs are internally pulled up to Vcc by a 100kΩ resistor, so simply using a GPIO should work. If you really need a the behavior you describe you can set the output to LOW by digitalWrite(pin, LOW) and make pulses by alternating pinMode(pin, INPUT) and pinMode(pin, OUTPUT).