Overview. NXP Elftosb

Freescale Semiconductor

User's Guide

Document Number: KBLELFTOSBUG

Rev. 1, 04/2016

Kinetis Elftosb User's Guide

1 Overview

The elftosb tool creates a binary output file that contains the user's application image along with a series of bootloader commands. The output file is known as a "Secure Binary" or

SB file for short. These files typically have a .sb extension.

The tool uses an input command file to control the sequence of bootloader commands present in the output file. This command file is called a "boot descriptor file" or BD file for short.

The Elftosb tool is command line driven and can be separately built to run on Windows

®

OS, Linux

®

OS, and Apple Mac

®

OS. The Kinetis bootloader package contains the executable for all the three targets.

This document describes the usage of elftosb in terms of its command line parameters, input command file (.bd) structure, and contents of the output .sb file. The below block diagram describes the operation of elftosb at a high level, working on the inputs passed on command line such as image file, BD file,

Key file, etc., and processing contents of the BD file to generate the output SB file.

Contents

1 Overview....................................................................1

2 Command line interface............................................ 2

3 Command file.............................. ............................. 4

4 elftosb key file format....................... ......................23

5 Appendix A: Command file grammar..................... 23

6 Appendix B: SB boot image file format.. ............... 26

7 Revision history.......................... ............................ 42

© 2016 Freescale Semiconductor, Inc.