On Sun, 2009-09-27 at 14:27 -0500, driveoldford wrote: > Here goes: > linux-w5px:/proc # chmod 777 /dev/ttyS* > linux-w5px:/proc # ls -l /dev/ttyS* > crwxrwxrwx 1 root uucp 4, 64 2009-04-14 06:32 /dev/ttyS0 > crwxrwxrwx 1 root uucp 4, 65 2009-04-14 06:32 /dev/ttyS1 > crwxrwxrwx 1 root uucp 4, 66 2009-04-14 06:32 /dev/ttyS2 > crwxrwxrwx 1 root uucp 4, 67 2009-04-14 06:32 /dev/ttyS3 > crwxrwxrwx 1 root uucp 4, 68 2009-04-14 06:32 /dev/ttyS4 > crwxrwxrwx 1 root uucp 4, 69 2009-04-14 06:32 /dev/ttyS5 > crwxrwxrwx 1 root uucp 4, 70 2009-04-14 06:32 /dev/ttyS6 > crwxrwxrwx 1 root uucp 4, 71 2009-04-14 06:32 /dev/ttyS7 > To my way of thinking this is a bug in your distro: since UDEV peripheral management came in the system probes the hardware at boot time and builds an entry in the /dev directory for everything it finds. This implies that it should not set up device names for non-existent devices. The extras will never be used since, if you plug in a USB device with serial ports these are all called /dev/ttyUSB* How many physical serial ports does each system have? Assume anything that exists is numbered from zero and only use items in that range. You could also try limiting it to reality by adding the 8250.nr_uarts=6 kernel argument to the GRUB boot command line Its usually in /boot/grub/grub.conf and you should add it to the end of the first 'kernel' line in the file. Needless to say, the number after the '=' is the number of serial ports you actually have - I have six. > Is this an old Bios issue? > No. AFAIK Linux doesn't use the BIOS at all. However, the GRUB boot loader does: the BIOS starts it and then it uses BIOS disk access calls to read the Linux kernel into memory. Once that's done it is overwritten and vanishes. Martin
