Tom Horsley wrote: >Did you add the kernel boot parameter in grub.conf? Mine looks like >this: >title Fedora (2.6.23.8-63.fc8) > root (hd0,2) > kernel /vmlinuz-2.6.23.8-63.fc8 ro root=LABEL=F8ROOT64 quiet 8250.nr_uarts=9 > initrd /initrd-2.6.23.8-63.fc8.img >The "9" as the value for 8250.nr_uarts tells the kernel to allocate slots >for 9 serial ports in its internal tables. The default is only 4. I use >9 to get the 1 native serial port on my motherboard plus the 8 ports in >my 8 port card to work. >(Of course if you are booting the Xen kernel, completely different trickery >is required). I fiddled around with this (I tried values of 5, 6, 7 & 8) until I found that this title Fedora (2.6.23.9-85.fc8) root (hd0,1) kernel /vmlinuz-2.6.23.9-85.fc8 ro root=/dev/VolGroup00/LogVol00 quiet 8250.nr_uarts=8 initrd /initrd-2.6.23.9-85.fc8.img gave this: ls -l /dev/ttyS* crw-rw---- 1 root uucp 4, 64 2008-01-11 15:39 /dev/ttyS0 crw-rw---- 1 root uucp 4, 65 2008-01-11 16:00 /dev/ttyS1 crw-rw---- 1 root uucp 4, 66 2008-01-11 15:39 /dev/ttyS2 crw-rw---- 1 root uucp 4, 67 2008-01-11 15:39 /dev/ttyS3 crw-rw---- 1 root uucp 4, 68 2008-01-11 17:35 /dev/ttyS4 crw-rw---- 1 root uucp 4, 69 2008-01-11 16:00 /dev/ttyS5 crw-rw---- 1 root uucp 4, 70 2008-01-11 16:00 /dev/ttyS6 crw-rw---- 1 root uucp 4, 71 2008-01-11 16:00 /dev/ttyS7 /bin/setserial -ag /dev/ttyS* /dev/ttyS0, Line 0, UART: unknown, Port: 0x03f8, IRQ: 4 Baud_base: 115200, close_delay: 50, divisor: 0 closing_wait: 3000 Flags: spd_normal skip_test auto_irq /dev/ttyS1, Line 1, UART: undefined, Port: 0x02f8, IRQ: 3 Baud_base: 921600, close_delay: 50, divisor: 0 closing_wait: 3000 Flags: spd_normal skip_test auto_irq /dev/ttyS2, Line 2, UART: unknown, Port: 0x03e8, IRQ: 4 Baud_base: 115200, close_delay: 50, divisor: 0 closing_wait: 3000 Flags: spd_normal skip_test auto_irq /dev/ttyS3, Line 3, UART: unknown, Port: 0x02e8, IRQ: 3 Baud_base: 115200, close_delay: 50, divisor: 0 closing_wait: 3000 Flags: spd_normal auto_irq /dev/ttyS4, Line 4, UART: 16550A, Port: 0x1030, IRQ: 21 Baud_base: 115200, close_delay: 50, divisor: 0 closing_wait: 3000 Flags: spd_normal skip_test /dev/ttyS5, Line 5, UART: 16550A, Port: 0x1028, IRQ: 21 Baud_base: 115200, close_delay: 50, divisor: 0 closing_wait: 3000 Flags: spd_normal skip_test /dev/ttyS6, Line 6, UART: 16550A, Port: 0x1020, IRQ: 21 Baud_base: 115200, close_delay: 50, divisor: 0 closing_wait: 3000 Flags: spd_normal skip_test /dev/ttyS7, Line 7, UART: 16550A, Port: 0x1018, IRQ: 21 Baud_base: 115200, close_delay: 50, divisor: 0 closing_wait: 3000 Flags: spd_normal skip_test with the four ports correctly assigned, BUT - alas I can't get the ports to work. A Qt program that works in Windows does not work in Linux - no communication. I've tried echoing a command to S4-7 - no luck. Qt (i.e. QIODevice & qextserialport) reports that the ports are open when I try to open them, but thats it. I've no idea what to do next, except to buy a different serial card that works in both Linux and Windows - perhaps it's something to do with the combination of motherboard and serial card? DS Looking for the perfect gift? Give the gift of Flickr! http://www.flickr.com/gift/