well, first of all, i am using rh7.1 on a thinkpad 380z, kernel 2.4.2-2 (as furnished with the distribution). since i have been stymied in the past in trying to compile kernels, i got only the two disk set from cheapbytes this time which doesn't seem to include the kernel source. i.e. /usr/src contains only redhat, and that seem to contain only empty directories. nor does there seem to be any kernel stuff on the two disks that i can see. but . . . i did look in /lib/modules/2.4.2-2/kernel/drivers/usb/serial and did an insmod for: usbserial, keyspan, keyspan_pda, and mct_u232, all of which showed up in lsmod, to wit: mct_u232 4160 0 (unused) keyspan_pda 6288 0 (unused) keyspan 16096 0 (unused) usbserial 13200 0 [mct_u232 keyspan_pda keyspan] pcnet_cs 10656 1 8390 6816 0 [pcnet_cs] autofs 11264 1 (autoclean) usbnet 9904 0 (unused) aha152x_cs 33113 0 scsi_mod 95104 1 [aha152x_cs] ds 7280 2 [pcnet_cs aha152x_cs] yenta_socket 11440 2 pcmcia_core 43072 0 [pcnet_cs aha152x_cs ds yenta_socket] ipchains 38976 0 (unused) cs4232 3440 0 ad1848 17904 0 [cs4232] uart401 6768 0 [cs4232] sound 62688 0 [cs4232 ad1848 uart401] soundcore 4464 4 [sound] usb-uhci 20720 0 (unused) usbcore 49664 1 [mct_u232 keyspan_pda keyspan usbserial usbnet usb-uhci] this would seem to indicate usb support via modules. i have both photopc and modem linked to ttyUSB0, and ttyUSB0 with all permissions: lrwxrwxrwx 1 root root 7 Feb 3 14:44 modem -> ttyUSB0 lrwxrwxrwx 1 root root 7 Feb 3 15:07 photopc -> ttyUSB0 crwxrwxrwx 1 root uucp 188, 0 Mar 23 2001 ttyUSB0 none the less, the device seems not to be there, giving these errors: sirius:moylan:~ [1007] photopc query Error 19: open /dev/photopc error No such device eph_open failed efax: 44:42 compiled Aug 30 2000 15:41:09 efax: 44:42 Error: can't open serial port /dev/modem: No such device efax: 44:42 failed -> tx0103a.001 efax: 44:42 done, returning 2 (unrecoverable error) i probably have some terrible misconceptions, but there you have it. thanks for the suggestions. dan peter wood said: > You probably need the USB Serial Converter kernel support. > If you are using a 2.4 series kernel, it should be pretty easy to enable. > In the kernel config make sure you have enabled usb support. Then, > while you're in the usb support section, you should find 'USB Serial > Converter Support'. Go into that section, enable usb serial support > (first option) and then enable the modules for which ever of the > selections seems apropos to your needs. Then just build all the new > kernel modules and you're set to go. There is more info on > Sourceforge, I think the project is just called usbserial. > This is what the Handspring Visor and the Keyspan USB PDA adapter > use to connect. It basically creates serial devices that hook in to USB. > For example /dev/ttyUSB01 can be used just like any other serial > device. > Here are the basic config options you'll need, in case you config your > kernel manually: > CONFIG_USB=m > CONFIG_USB_SERIAL=m > And then the specific driver - here, for example, the Keyspan USB > Serial PDA adapter. > CONFIG_USB_SERIAL_KEYSPAN_PDA=m > Let me know if this is unclear. It's been a while since I had USB on a > Linux box so I'm a little hazy, but I think that's the general idea. charles bennett said: > Assuming you have a RedHat 7-ish system with a 2.4.x kernel, look in > /usr/src/linux-2.4/Documentation/usb. > The files usb-serial.txt and hotplug.txt are probably apropos. > dan moylan said: >> >> i possess a usb to serial adaptor. >> >> lsmod shows the following: >> >> usbnet 9904 0 (unused) >> usb-uhci 20720 0 (unused) >> usbcore 49664 1 [usbnet usb-uhci] >> >> i see no man pages related to usb at all, at least >> man -k usb shows nothing. j. daniel moylan 84 harvard ave #2 brookline, ma 02446-6202 617-232-2360 (tel) 810-454-1823 (fax) jdm34@cornell.edu moylan.info