Getting serial console working

[Rabeeh Khoury]

For Linux -
http://www.openplug.org/plugwiki/index.php/Setting_up_Serial_Console_Under_Linux

For Windows -

http://www.openplug.org/plugwiki/index.php/Configure_u-Boot_on_the_Plug_Computer

Combined wiki page -

http://www.openplug.org/plugwiki/index.php/Serial_terminal_program

[moshiach]

Any ideas what kernel options/extra programs might be needed to get linux to actually create those ttyUSB endpoints?  I've rebuilt my kernel a couple of times today with leds from various websites about using usbserial as a module but have been unable so far to get it to create ttyusb0 ttyusb1.  I hate having to turn on my work laptop just to read the console.

[Rabeeh Khoury]

I just use standard kernel with any standard distro.
It should have the ftdi chip drivers.

[cslee]

I've connected to the plug via hyperterm. It's asking me for user name and password. What would that be?

[cslee]

ignore my post. I found the answer on another forum

[moshiach]

I'm still having difficulty getting the console to work in linux.  I jsut booted into a Ubuntu enviroment (someone on IRC mentioned that "it just works" in ubuntu) and was still unable to get TTYUSB0 in my dev.

A couple of things I've tried:
1) rebuilt my kernel with usbserial as a module
2) setup ftdi_sio as a module
3)  Loaded both modules
4) Plugged in the unit and reset it with the handy dandy reset pin pusher.

I've even tried making my own ttyUSB0 node with mknod /dev/ttyUSB0 c 188 0.

No joy.  I can see thorugh DMESG and /var/log/messages that the unit is seen (although not recognized i.e no name) by usb.  It puts a /dev/usb device name file, but no tty.   I can of course see it perfectly in windows, but I do all my developement on the linux box and switching over to windows to see the console is getting annoying.


Anyone have any ideas how to get linux to see the unit so minicom can read it?

[moshiach]

Finally!  I forget what led me to this document but it was the final piece I needed to get my kernel to recognize the serial usb console for the plug in Linux.

1)  Make sure your kernel has usbserial (I compiled it as a module rather than built-in since I don't need it cluttering up my memory when it's not needed)  Device Drivers->USB->USB Serial Converter
2)  In the same section, compile USB FTDI Single Port Serial Driver as a module  Device Drivers->USB->USB Serial Converter->USB FTDI Single Port Serial Driver (experimental)

Reboot to the new kernel.  Plug in your sheeva and modprobe ftdi_sio product=0x9e8f vendor=0x9e88   And there you have it.  A working ttyUSB1 that you can access with a terminal program.  It's the product and vendor id's that ftdi_sio needs to match the device to the tty.

Strangely enough my udev rule doesn't match it, but I'm sure I can figure that part out as well.

[moshiach]

Ok!  One problem down, 2 left.

The following udev rules will automatically detect and load the modules for sheevaplug, and as an added bonus will remove those modules when it's disconnected.

SYSFS{idProduct}=="9e8f",SYSFS{idVendor}=="9e88",ACTION=="add",RUN+="/sbin/modprobe -q ftdi-sio product=0x9e8f vendor=0x9e88"
ENV{PRODUCT}=="9e88/9e8f/500",ACTION=="remove",RUN+="/sbin/rmmod ftdi_sio usbserial"

Progress is being made!  Now I jsut need to solve the mysterious mtdparts kernel command not working and then maybe I can finally flash the provided kernel and rootfs.  After that it's just a matter of fixing my kernel compilation issue and I'm finally in business.

[ben]

Thanks for the tip on modprobe ftdi_sio product=0x9e8f vendor=0x9e88.  I now have ttyUSB0 and ttyUSB1!   

This should be added to the wiki.  Maybe I will get some time after a while and add it.

Thanks,
Ben

[jlpoole]

For the record, I had intermittent problems when I connected to my SheevaPlug from my Dell 620 using the serial port (hardwired).  The symptoms where the SheevaPlug completely resetting occasionally, like once every hour or two.  I mistakenly thought the resets were arising from a USB hub and posted to this forum, but later concluded that the resets occurred only if I remained connected using the serial port. 

I avoid using the serial port, or if I use it I keep my connection time to a short duration, and simply log in using PuTTY through an ssh connection -- the reset problems disappeared and the SheevaPlug has been completely stable.

[badcam]

This thread has helped me a lot. I've managed to get puTTy working on Puppy Linux and talking nicely with the Sheevaplug, either as SSH or via the mini USB uboot function. Sweet.

The crux was the modprobe ftdi_sio product=0x9e8f vendor=0x9e88

Thanks very much.

[badcam]

I note that whenever I restart I have to use the "modprobe ftdi_sio product=0x9e8f vendor=0x9e88" command each time.

In which file do I save this so that it's remembered upon reboot? Thanks.

[birdman]

In which file do I save this so that it's remembered upon reboot? Thanks.

Try:
 /etc/udev/rules.d/10-My-PlugConsole.rules

[pallinger]

My problem was that although /dev/ttyUSB0 appears, /dev/ttyUSB1 does not appear, and I can't connect to /dev/ttyUSB0 with any terminal program.
It does not matter if I let udev do the module loading or I load ftdi_sio manually.

Finally!  I forget what led me to this document but it was the final piece I needed to get my kernel to recognize the serial usb console for the plug in Linux.

I've read the above document, and it gave a tip about removing the brltty package, which I did.
After that, there was still no /dev/ttyUSB1, but I could connect to /dev/ttyUSB0 with gtkterm. Hoorray!

Someone should put this info into the wiki, as it is really useful for ubuntu users...

[plugcrazy]

unable to get to the serial port from my windows xp laptop. trying to set the port settings does not seem to be working. Tried to assign different com ports to the USB serial port in the Device Manager config. Both Teraterm and Putty are not responding!

And to top it all I screwed up on the root password!!! :-((((((((((((

HELP!