Re: fedora 27 on inet 3f tablet with newer kernel from repo does not boot anymore

[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]

 



> > when i enable the original dtb file, the board is now working, I am
> > however succeeded in soldering a serial connection to the board.
> > 
> > The only strange thing is when i send from one side:
> > 
> > echo -en '\x00' > /dev/ttyS0          i receive 0x00 in hex
> > echo -en '\x01' > /dev/ttyS0          i receive 0x7F in hex
> > 
> > --> this makes the serial output unreadable since the mapping of
> > characters seems to be off, does anyone has an idea how to fix
> > this?
> > 
> > --> i tried this with a baudrate of 300 to be sure the connection
> > is
> > stable.
> 
> All Allwinner devices I've seen use a rate of 115200, it may be that
> the serial port isn't enabled by default in u-boot and/or the
> DeviceTree because of it being a tablet and it not having one by
> default so you might nee to look at what needs to change for that to
> work.

its not really clear to me, but since i am capable to send data over in
hex, its seems that its enabled and also working on a rate of 300.
Because when i send '\x01\x01' i receive 0x7f7f on the receiver side.
Just to be clear i opened the serial terminal on my tablet as well
(from within fedora running on tablet) at a baudrate of 300.

Could it be that the dts is using the wrong serial device driver?
Are there many different serial drivers for the allwinner a10?
I am using this one:
		serial@01c28000 {
			compatible = "snps,dw-apb-uart";
			reg = <0x1c28000 0x400>;
			interrupts = <0x1>;
			reg-shift = <0x2>;
			reg-io-width = <0x4>;
			clocks = <0x3c 0x10>;
			status = "okay";
			pinctrl-names = "default";
			pinctrl-0 = <0x3d>;
		}; 

I might be able to find out which serial device is used in the android
fex files.

> > --> i tried to attach my serial output to the input of the pc and
> > that
> > return fine, so it seems the 2 serial ports are actually speaking
> > another dialect.
> > 
> > > _______________________________________________
> > > arm mailing list -- arm@xxxxxxxxxxxxxxxxxxxxxxx
> > > To unsubscribe send an email to arm-leave@xxxxxxxxxxxxxxxxxxxxxxx
> > 
> > _______________________________________________
> > arm mailing list -- arm@xxxxxxxxxxxxxxxxxxxxxxx
> > To unsubscribe send an email to arm-leave@xxxxxxxxxxxxxxxxxxxxxxx
_______________________________________________
arm mailing list -- arm@xxxxxxxxxxxxxxxxxxxxxxx
To unsubscribe send an email to arm-leave@xxxxxxxxxxxxxxxxxxxxxxx




[Date Prev][Date Next][Thread Prev][Thread Next][Date Index][Thread Index]
[Index of Archives]     [Linux ARM (Vger)]     [Linux ARM]     [ARM Kernel]     [Fedora User Discussion]     [Older Fedora Users Discussion]     [Fedora Advisory Board]     [Fedora Security]     [Fedora Maintainers]     [Fedora Devel Java]     [Fedora Legacy]     [Fedora Desktop]     [ATA RAID]     [Fedora Marketing]     [Fedora Mentors]     [Fedora Package Announce]     [Fedora Package Review]     [Fedora Music]     [Fedora Packaging]     [Centos]     [Fedora SELinux]     [Coolkey]     [Yum Users]     [Tux]     [Yosemite News]     [Linux Apps]     [KDE Users]     [Fedora Tools]     [Fedora Art]     [Fedora Docs]     [Asterisk PBX]

Powered by Linux