i.MX6ULL USB_OTG2 ROM loader

[chris321]

Hello,

according to the i.mx6ULL reference manual it is possible to use both USB OTG ports for ROM loading purposes.

Is the USB_OTG_ID pin analyzed by the ROM?

I want to use the USB_OTG2 port for manufacturing a custom board and after that it should be in host mode.

I plan to use the following pads for the muxable USB signals:

usb_otg2_id -->GPIO1_IO05

usb_otg2_oc --> SD1_DATA2

usb_otg2_pwr -->SD1_DATA1

I have a reference kit (compute module + base board) on my desk.

Is it possible to force the ROM loader to use the USB_OTG2 interface somehow?

[igorpadykov · Accepted solution]

Hi chris321

USB_OTG_ID pin is not analyzed by the ROM. Also only USB_OTG1

is used by ROM according to i.MX6ULL Reference Manual sect.8.2.4 Serial Downloader

https://www.nxp.com/docs/en/reference-manual/IMX6ULLRM.pdf 

Best regards
igor
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[chris321]

Hi Igor, thank you for this answer.

According to the Reference Manual sect 8.9.1:

"The ROM supports the USB OTG port for boot purposes. The other USB ports on the chip are not supported for boot purposes."

I thought all the OTG ports are available for boot purposes.