STM32 Custom Bootloader (Part 3): Application Size & CRC Validation

Build a *more reliable STM32 bootloader* that verifies the application size and CRC32 before jumping to it, ensuring that only a complete and uncorrupted firmware image is executed. In this tutorial, we continue the STM32 custom bootloader series and extend the application validation with *size and CRC32 checks*. We add the application size and CRC to the application header, generate a CRC-ready binary without the header, and use a Python script to calculate the application size and CRC value. The bootloader checks the magic number, reset handler, application size, and calculated CRC before allowing the jump to the application. We also test both valid and corrupted firmware images, showing how the bootloader detects a CRC mismatch, reports the error through UART, and blocks the application from running. #STM32 #STM32Bootloader #EmbeddedSystems #Bootloader 📁 *Download Project Files & Full Article:* https://controllerstech.com/stm32-bootloader-application-crc-size-validation/ 📁 *STM32 Tutorials:* https://controllerstech.com/stm32-tutorials/ 📁 *ControllersTech Home:* https://controllerstech.com/ ### ▶︎ Related Videos 1️⃣ *Application Validation Using Magic Number:* https://youtu.be/w1NorigAWJA 2️⃣ *Implement OTA FLAG Mechanism:* https://youtu.be/t7Lcx4RigB0