On Wed, 29 Sep 2010 11:55:21 -0400 "Roger K. Wells" <ROGER.K.WELLS@xxxxxxxx> wrote: > > I have a RS485 serial device (Quatech SSU2-300) that when plugged > into a USB (2.0) port appears to be recognized correctly. dmesg yields: > > cp210x 3-1:1.0: cp210x converter detected > usb 3-1: reset full speed USB device using uhci_hcd and address 8 > usb 3-1: cp210x converter now attached to ttyUSB0 > > A "C" language program attempting to use this port hangs at the > open call. > > This same program with the same device worked on a Centos 5.5 > install on the same computer. > > uname -r : 2.6.34.7-56.fc13.x86_64 > > The USB device works in Windows XP so I don't think there is a defect > there. Modern kernels properly handle carrier detect and wait so open it with O_NDELAY if you don't want to wait for the carrier line to be asserted and/or set the CLOCAL termios bits if you are not using the carrier and flow control. -- users mailing list users@xxxxxxxxxxxxxxxxxxxxxxx To unsubscribe or change subscription options: https://admin.fedoraproject.org/mailman/listinfo/users Guidelines: http://fedoraproject.org/wiki/Mailing_list_guidelines
