Interfacing STM32 F401xx with Keypad

Note: STM32 Nucleo Board with F401xx microcontroller is used for interfacing. The programming is completely baremetal without the use of CubeMX software.

Requirements

Hardware

• STM32 F401xx based Nucleo Development Board
• Relay
• LED
• Resistor 220Ω

Software

• STM32 Cube IDE

Additional Code

• The printf() function cannot be executed by default.
• Some additional code is added in "Src\syscalls.c" file which makes use of the SWO trace pin to print statements.

Demo

stm32_relay.mp4

Circuit Diagram