AnsweredAssumed Answered

Kinetis Bootloader for K22FX

Question asked by Ciprian Anton on Sep 15, 2015
Latest reply on Nov 6, 2015 by Ernesto Lopez

Hi Freescale Community,


I'm trying to make the kinetis bootloader work on MK22FX512VLL12 using the USB HID interface.

The reference target that I used is MK22F51212 from the kinetis bootloader project. I have tested the reference project on FRDM-K22 (has MK22FN512VLH12  MCU)  and it works.


In order to make the project work on my MCU (MK22FX512VLL12) first thing I did was configuring the system clock to work on external reference clock (This MCU don't have internal IRC48). The clock configuration is PEE (PLL Engaged External) working with an 8 MHz crystal. The MCG is set to give 48 MHz (I saw that the USB module needs this freq). MCGPLLCLK is also enabled.

I also changed the header file (MK22F51212.h) to add support for the FTFE flash controller (the default is FTFA flash controller).


The problem I have is that USB communication is not working and I can't figure why. The windows tells that there is an Unknown Device. The product id and vendor id are also unknown.


I've put some breakpoints in the USB IRQ (_usb_dev_khci_isr) and the following intrerrupts are issued:




Any help would be appreciated,