How to keep USB alive while entering bootloader?

cancel
Showing results for 
Show  only  | Search instead for 
Did you mean: 

How to keep USB alive while entering bootloader?

714 Views
georgschmidt
Contributor III

Hi,

I'm working on a USB-Bootloader for my Kinetis K60 project.

I have to seperate projects (bootloader and application) stored in different Flash-sections.

Currently I'm able to jump from application to bootloader and back.

The problem is, that I loose the USB-connection (running on USB0-module) after jumping from one section to the other.

If I do a complete reinitialisation of the USB, the USB disconnects and reconnects imediately after the jump.

But I don't want the PC to recognize the jump, so I have to recover some settings of the USB-module.

But which?

I tried to recover the BDT-Table contents, but this seems not to be enough. Do I need to recover the Endpoint-Buffers also?

Has anyone done something like this without using a RTOS or Processor Expert?

Regards,

Georg

Labels (1)
Tags (2)
2 Replies

507 Views
juanma_clautron
Contributor II

Hi Georg!

How do you jump from the app to the bootloader "Currently I'm able to jump from application to bootloader and back." ???

Thanks

0 Kudos

507 Views
Jorge_Gonzalez
NXP Employee
NXP Employee

Hello Georg:

I think the jump cannot be transparent for the PC. The bootloader and the application do not share the same BDT table, instead each one has its table, and the transition is detected, so as you mentioned you need to reinitialize the USB.


Regards!,
Jorge Gonzalez