Mark Butcher

Kinetis Boot Loader for SREC UART, SD Card and USB-MSD loading

Discussion created by Mark Butcher on Dec 20, 2013
Latest reply on Feb 25, 2018 by Luis Hernandez Salvador

Hi All


There has always been a high demand for boot loader solutions and the uTasker project includes a number of these which have proven to be quite popular, even for use with applications from different sources.


The demands as to how the loader operates are quite varied and so a flexible loader has been put together which allows the following modes of boot loader operation in one single loader:

- UART S-REC loading at 115200 Baud

- SD Card loading (a new software is copied to an SD card and inserted)

- USB-MSD (the board apears as a disk drive and the software can be copied)


This allows all of the three possibilites to be used in a compatible manner. The boot loader size (with all modes enabled together) is about 25k. If some modes are not required they can be mixed as necessary in the project and so much smaller Flash size needed.


For K60 Tower Kit users there is a package at µTasker Test Software and Demos which allows it to be used immediately for any application up to 130k in size. The loader is documented at and there is also a video showing its flexible operation at Kinetis K60 Tower Kit - Flexible Boot Loader - YouTube


Note that the complete package also supports encryption (to allow code distribution without reverse enginering possibility), USB-DFU, HS-USB and Ethernet loader (Web Server based - about 18k Flash) for chips with Ethernet.