The trick is simple, but not obvious:


echo "disallow method ppdev" > /etc/ieee1284.conf


Never ever move your buildroot directory because it does not like it.

I have recently tried to breathe life to the serial port of my DELL D630 notebook under Ubuntu Natty, but the opening always failed with I/O error.

I have tried the relevant acpi=off, pnpacpi=off kernel parameters, updated the BIOS, but these thigns did not lead to succes. As final trying I have switched the port from COM1 to COM2 int the BIOS and finally it became available as /dev/ttyS1

I have tried to use the Lattice ispVM under Ubuntu 11.04, with the Lattice USB download cable, but I have to run it as root, even after adding the udev rules mentioned in the FAQ.

After some strace analyzing I have figured out that it is trying to open the /dev/bus/usb/{roothub}/{devide} nodes. Since then the download cable's node was read only it failed.

I have written the following udev rule to the /etc/udev/rules.d/51-lattice.rules file inspired by my AVR doper's rule:


SUBSYSTEM=="usb", ACTION=="add", ATTR{idVendor}=="1134", ATTR{idProduct}=="8001", MODE="0666"


Or anything else what is modifying somehow the output of the GCC.
Otherwise you will suck like a gluttonous badger* like I did.

A.k.a torkos borz in hungarian.