Input pin in pull up mode is being in high impedance state

Vladyslav8989 · ‎2025-09-17

I have set PA3 pin as input with pull up mode. But testing this pin by multimeter I get high impendance state (0.5V) on it. Must be 3.3V (logical 1). I use stm32F417ZGT6.

Andrew Neil · ‎2025-09-17

welcome to the forum.

Please see How to write your question to maximize your chances to find a solution for best results.

In particular, Please give details of your hardware.

A complex system that works is invariably found to have evolved from a simple system that worked.
A complex system designed from scratch never works and cannot be patched up to make it work.

TDK · ‎2025-09-17

The attached code initialized PA3 as input with pullup. No problems there. Nothing special about PA3.

The issue is likely with your hardware. It's also possible you're not measuring the actual pin. Show a picture of your setup, schematic, and what you're actually measuring.

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