How to use USB OTG on A20 as USB Serial?

mushketer888 · October 11, 2014, 11:58:00 PM

How to use USB OTG on A20 as USB Serial?
For example i want to use Olinuxino's USB OTG as usb-serial interface with PC

mushketer888 · October 12, 2014, 02:21:19 PM

Just some suggestions would be enough

JohnS · October 12, 2014, 03:49:37 PM

PC as host, so not using A20 as OTG but instead as device. Sounds like USB CDC.

John

nn · October 14, 2014, 10:00:30 PM

Maybe you need the gadget_serial module. See:

linux-sunxi/Documentation/usb/gadget_serial.txt

It works for me to get a serial login on the USB.

jmss · October 28, 2014, 09:16:15 PM

Quote from: nn on October 14, 2014, 10:00:30 PM
linux-sunxi/Documentation/usb/gadget_serial.txt

Where is this file?

Thanks.

JohnS · October 28, 2014, 10:37:22 PM

google for it and then try the obvious Documentation/usb/gadget_serial.txt

John

jmss · October 28, 2014, 11:46:46 PM

Quote from: JohnS on October 28, 2014, 10:37:22 PM
google for it and then try the obvious Documentation/usb/gadget_serial.txt

John

I found this one:

https://www.kernel.org/doc/Documentation/usb/gadget_serial.txt

but I thought it would be something specific.

jmss · October 28, 2014, 11:57:11 PM

Will this gadget_serial work for making A20 behave as a keyboard for an Android tablet on the other end of the USB cable?

MBR · November 02, 2014, 09:06:12 AM

Quote from: jmss on October 28, 2014, 11:57:11 PM
Will this gadget_serial work for making A20 behave as a keyboard for an Android tablet on the other end of the USB cable?

No, for keyboard (and any other "normal" USB input device) you will need the HID Gadget, see https://www.kernel.org/doc/Documentation/usb/gadget_hid.txt.