SDAA064 November   2025 F29H850TU , F29H859TU-Q1

 

  1.   1
  2.   Abstract
  3. 1Introduction
  4. 2Building Blocks for LFU
  5. 3Details of Proposed Design
    1. 3.1 Flash Bank Organization
    2. 3.2 LFU Concepts and Factors Impacting Performance
    3. 3.3 Hardware Support for LFU
      1. 3.3.1 A/B Swappable Flash Banks
      2. 3.3.2 Interrupt Vector Table Swap
  6. 4Application LFU Flow
  7. 5Results and Conclusion
  8. 6Example Implementations
  9. 7Summary
  10. 8References

1 Introduction

In applications like server power supplies, the system is desired to be run continuously to reduce downtime. Typically, during firmware upgrades - due to bug fixes, new features, and/or improvements - the system is removed from service causing downtime. This can be handled with redundant modules but with an increase in total system cost. An alternate approach, called Live Firmware Update (LFU), allows firmware to be updated while the system is still operating.

On F29x MCUs, switching to new firmware can be done both with and without a device reset. This user guide is for switching without reset. For an implementation with reset, see Firmware-Over-The-Air Upgrade Example for F29H85x. Please note that this example is for HS-FS (i.e. nonsecure) devices.