Cannot disable PullUp on GPIO18
Posted: Tue Nov 07, 2023 2:08 pm
Hello everyone,
I'm working on an ESP32S2 and I must read an analog value from GPIO18.
I am successful in reading a correct value from the pin; however, the voltage on the pin never fell below 0.5V (even with an external pulldown resistor), which prompted me to do some experiments.
I started fiddling with an ESP32S2-Devkit-m1 and configured the GPIO18 as a floating input: the result was the same, with the analog level on the pin being 3.3V without anything connected to it. With a pulldown (2KOhm) it falls to about 0.5V.
Is there a special configuration for the GPIO18? I could find nothing specific on the datasheet or other documents. It's the default RX pin for UART1, but I'm not using it in my project.
I'm working on an ESP32S2 and I must read an analog value from GPIO18.
I am successful in reading a correct value from the pin; however, the voltage on the pin never fell below 0.5V (even with an external pulldown resistor), which prompted me to do some experiments.
I started fiddling with an ESP32S2-Devkit-m1 and configured the GPIO18 as a floating input: the result was the same, with the analog level on the pin being 3.3V without anything connected to it. With a pulldown (2KOhm) it falls to about 0.5V.
Is there a special configuration for the GPIO18? I could find nothing specific on the datasheet or other documents. It's the default RX pin for UART1, but I'm not using it in my project.