UART-Based Boot Loader for the F6482 Series of MCUs

This application note describes the design of a boot loader program that resides in a reserved area of Flash memory on the F6482 Series of MCUs, a member of Zilog’s Z8 Encore! XP family. The boot loader can be used to update an application in the non-reserved area of Flash without the operator having to install the complete Zilog Development Studio (ZDS) Integrated Development Environment (IDE). This allows the application firmware to be field-upgraded to provide new or updated features after the device has been deployed to end-customers.

The UART-based boot loader is a tiny assembly language program (less than 1 KB in size) that implements an interactive console over one of the integrated UART devices on the F6482 series. Menu commands are used to erase the existing application from Flash memory, download a new firmware image in Intel Hex format, and then restart the system for the new application program to take effect.