topic Re: USB example crashed when it ran from SDRAM in i.MX RT Crossover MCUs

USB example crashed when it ran from SDRAM

jasonedn — Sat, 02 Jan 2021 04:18:39 GMT

It worked when the usb example "dev_audio_generator_bm" ran from qspi flash on rt1020evk. However it crashed when it ram from SDRAM. It always crashed at USB_DeviceEhciSetDefaultState(). Actually it crashed only after ehciState->registerBase->DEVICEADDR = 0U in USB_DeviceEhciSetDefaultState().

Re: USB example crashed when it ran from SDRAM

danielchen — Sun, 03 Jan 2021 01:57:04 GMT

Hi @jasonedn

Please refer to below article for your issue

https://community.nxp.com/t5/i-MX-RT-Knowledge-Base/Using-NonCached-Memory-on-i-MXRT/ta-p/1183369

Regards

Daniel

Re: USB example crashed when it ran from SDRAM

h_bouchard — Mon, 29 Nov 2021 19:05:47 GMT

Hi @jasonedn,

Did you solve your problem? If so, how?

I'm also experiencing the same issue and the fix proposed by Daniel doesn't work. I put my entire code and data in ITCM and DTCM but it still crashes at line ehciState->registerBase->DEVICEADDR = 0U in USB_DeviceEhciSetDefaultState().

Funny thing is that it works without a debugger connected...

Thanks
Hugo

Re: USB example crashed when it ran from SDRAM

jasonedn — Mon, 06 Dec 2021 16:43:34 GMT

Hi Hugo,

It was fixed in my case by setting the following macros:

DATA_SECTION_IS_CACHEABLE =1

XIP_EXTERNAL_FLASH = 0

Cheers

Jason