I’ve just been playing with the new Angstrom image. Here’s a couple of pointers:
- Serial port garbage
This appears to be (for me anyway) a problem with the serial port going to sleep. Most of the time it just generates some junk which can be cleared with CTRL-U or backspace. However, if it happens at the login prompt then getty thinks the terminal is 7-bit with parity (rather than 8-bit raw). If this happens and you continue to login the whole session appears to be scrambled - if you press CTRL-D you can login again provided you don’t stop typing… :]
I have simply added the following two lines to root’s .profile:
stty -parenb -parodd cs8 -inpck -istrip
echo 0 > /sys/class/tty/ttyS2/device/sleep_timeout
A better fix would probably be to just add the second line to a rc.d startup script somewhere…
- USB CDC serial port
The demo image and a Narcissus built rootfs don’t put a login prompt on the serial-over-USB port. If you add the following line to /etc/inittab and then run “pkill -HUP init” then you can do a serial login over the USB connection from a USB host with minicom by connecting to /dev/ttyACM0.
GS:2345:respawn:/sbin/getty 115200 ttyGS0
Is there any reason why this isn’t there by default…?
- Kernel panic / division by zero errors
My Rev C2 board fails to boot the uImage from the demo directory… it panics… The same board boots a Narcissus kernel image (Linux beagleboard 2.6.32 #1 PREEMPT Thu Mar 18 10:33:56) but dmesg shows a couple of division by zero errors which didn’t cause a panic. I would include an output form the uImage that panics, but my laptop battery is about to die…!!