trying USB:
[noah@Noah empeg-car]$ ./emptool /dev/ttyUSB0
Unknown device character 188,0 - assuming serial buffering
4001 Failed to open device /dev/ttyUSB0, errno:13

then. i tried setting up a USB device in the manner that empeg suggests:
cd /dev
mknod empeg-car0 c 240 0
chmod 666 empeg-car0
ln -s empeg-car0 empeg-car

[noah@Noah empeg-car]$ ./emptool /dev/empeg-car
4001 Failed to open device /dev/empeg-car, errno:19

and if i try SERIAL:
[noah@Noah empeg-car]$ ./emptool /dev/ttyS0
4001 Failed to open device /dev/ttyS0, errno:16

but sometimes it will start connecting but tell me that it cant find a device and i should check the cabling (it doesnt seem to be predictable). I'm new to linux, and im reallly starting to get frustrated....