Embedded Design Handbook

ID 683689
Date 8/28/2023
Public
Document Table of Contents

5.3.4.6. Boot Copier Code Size

The advanced boot copier example, without modification, compiles to an executable file of size approximately 8500 bytes. If you turn off all the JTAG UART and system clock timer functionality, the example executable size is reduced to approximately 2000 bytes.

By comparison, the code size of the default boot copier, described in the “Default Nios® II Boot Copier” section, is approximately 200 bytes when compiled to boot from CFI flash, and approximately 500 bytes when compiled to boot from EPCS/EPCQ flash.

If you require a customizable boot copier that is smaller than 2000 bytes, refer to the “Small Boot Copier Example” section. The small boot copier is written in Nios® II assembly language, and includes very few features. When executed, it simply copies a boot record located in CFI flash to RAM, and then branches to the copied application. The compiled code size is approximately 200 bytes.