AN3299

Hardware

Doc ID 18113 Rev 1

7/13

1.3.1

Push-pull

Set the GPIO to output state through the GPDR (0x12) register. Input path is disabled.

Output path is enabled in push-pull configuration.

Figure 5.

GPIO push-pull configuration

1.3.2

Open drain

GPIO output driven low by STMPE801

Set the GPIO to output state through the GPDR (0x12) register. Input path is disabled. Set

the output state to low through the GPSR (0x11) register. Output path is enabled and GPIO

pin pulled low.

Figure 6.

GPIO open drain configuration (output low)

GPIO output pulled high by external pull-up resistor

Set the GPIO to input state through the GPDR (0x12) register. Input path is enabled and

output path disabled. GPIO is pulled high by the external pull-up resistor.