Martin Dusek

USB mass storage host

Discussion created by Martin Dusek on May 22, 2013
Latest reply on May 23, 2013 by Martin Dusek


is there anyone who managed to get USB mass storage host on Kinetis MCU reliably working?


I use Freescale USB stack 4.0.3 on bare metal K70. I managed to get working my USB host with most of sticks I have but I don't have the feeling that the application will work realiably.


I think kinetis USB host driver (khci_kinetis.c) is not written very well. I can see two main problems:


1) Changing CPU clock speed means that some sticks stops working with USB host.

2) Every transaction is once to 4 times nacked before the stick acknowledges it. I think it's a bug in driver, not problém of USB stick itself.

Is there any newer version of khci_kinetis.c?


Best regards