topic Re: k22 usb device descriptors in Kinetis Microcontrollers

k22 usb device descriptors

584069980 — Tue, 04 Aug 2020 02:34:59 GMT

I am using the MCU MK22FN512VLL12.My problem is that I can receive 8-byte device requests,
but the device descriptors can't be sent out. And Cause some Error flags, PIDERR BTOERR BTSERR

so what is the possible reason and how to solve this problem ?

Re: k22 usb device descriptors

FelipeGarcia — Thu, 06 Aug 2020 15:02:06 GMT

Hi Cai,

Could you please provide more details of your application? I recommend you to check the reference manual in chapter 43.4.11 Error Interrupt Status register (USBx_ERRSTAT). There you will find description about each error source that you might be falling into.

Best regards,

Felipe

Re: k22 usb device descriptors

584069980 — Fri, 07 Aug 2020 00:37:18 GMT

Thanks !

When the PC recognizes that there is a USB device inserted, it will send a device request. K22 will send device descriptors to the PC after receiving an 8-byte device request. That's the problem. K22 can't send device descriptors.The PC will not be able to enter the next configuration.

I know the reason of these errors, but I don't know how to deal with them。Which registers need to be modified

Best regards,

Cai

Re: k22 usb device descriptors

FelipeGarcia — Wed, 12 Aug 2020 22:54:32 GMT

Hi Cai,

If you have incorrect data being sent or expected the transfers will fail, which is presumably what is happening. Please check the below thread from a customer that was experiencing Turnaround Timeout error as well.

https://community.nxp.com/thread/308999

In addition, I recommend you to monitor USB traffic with a USB analyzer.

Best regards,

Felipe