This application note, with UART as an example, provides general guidelines for creating an IAP application using two different methods: the first one is based on the Ymodem protocol and the second one is based on a customized UART protocol using the free Flash Loader utility provided by ST.
This document outlines guidelines for creating an In-Application Programming (IAP) application for the STR91xFAxxx family of microcontrollers. It details two methods for reprogramming the MCU's embedded Flash memory while the system is installed: one based on the Ymodem protocol and another using a customized UART protocol with the ST Flash Loader utility.
The note provides specific instructions on hardware configuration, such as remapping Flash banks and triggering execution via a push button. It includes step-by-step procedures for downloading firmware images to internal Flash, verifying data integrity, and executing new programs, along with descriptions of the IAP driver code structure.
| IAP Driver Code Size (Ymodem) | approximately 7.5K |
|---|---|
| IAP Driver Code Size (Flash Loader) | approximately 6 Kbytes |
| UART Baud Rate Example | 115200 bps |
This application note uses UART as the example communication protocol.
Execution is triggered by pressing a push button connected to pin 4 of port 7 at reset.
The error message 'Verification failed' is displayed in the HyperTerminal window.