On Sun, Jul 25, 2010 at 09:01:06PM +0200, Ben Andersen wrote: > Hello, > > I have 3 USB devices connected which are part of a cash register. > > 1. USB Fiscal control unit (symlink: ttyS10) > 2. Serial Receipt printer on a USB2Serial converter (symlink: ttyS20) > 3. USB Customer display (symlink: ttyS30) > > I need to know which ttyUSB* each device gets. I solved this with a udev > rules file with symlinks to ttyS* which works fine. I had to make them > ttyS* and not something like /dev/receiptprinter to have them working > with the java lib rxtx, it seems they have to have a "serial port name". Sounds like a java library problem :) > The ttyS30 device does not work with the common lucid kernel. So I had > to get the latest generic kernel, else it just does not work at all. > > My only problem now is that the device that should come up as ttyS30 > sometimes does not map to any ttyUSB* and hence the ttyS30 symlink > points to bus something instead of ttyUSB* and the device is unusable. > If I don't connect the ttyS10 device this is not a problem so it seems > there is some kind of clash that sometimes prevents the ttyS30 device > from working. They're both using the same driver (ftdi_sio) while ttyS20 > is using pl2303. > > My udev rules are as follows: > http://paste.ubuntu.com/468897/ > > When it works it looks like this: > http://paste.ubuntu.com/468881/ > > When it does not work it looks like this: > http://paste.ubuntu.com/468882/ > > Note this line when it's not working.. > util_run_program: '/sbin/modprobe' (stderr) 'FATAL: Module > usb:v0519p0007d0400dc00dsc00dp00icFFiscFFipFF not found.' > > I tried changing the rules file to only using idVendor as unique > selection and it seemed to work at first but now it's the same again. > Sometimes it works, sometimes it does not when starting up the computer. > > It does always work it seems if plugging the ttyS10 device after startup > of the computer. > > One side problem is that this line never works: > ATTRS{idVendor}=="0519", ATTRS{idProduct}=="0007", RUN+="/bin/stty -F > /dev/ttyS30 19200" > It works running the line from cmd-line or the script which starts the > POS-software. BUT not when I autstart the script in Ubuntu (startup > programs). It seems it's too early for ttyS30 to be completely finished?? > > Thanks for any help in this matter! It would be fantastic if Ubuntu > would work better as a POS system. I'm using Openbravo POS btw. As this is a userspace udev issue, there's nothing that the kernel can do here really. I'd recommend using a device with a unique serial number, and/or using the /dev/serial/ symlinks to get the proper persistant device name for your devices, so no matter what happens with the devices being found in any order, it will all "just work". Oh, and go fix your java library, it shouldn't only work with old serial port names, that's a bad bug on its part. good luck, greg k-h -- To unsubscribe from this list: send the line "unsubscribe linux-usb" in the body of a message to majordomo@xxxxxxxxxxxxxxx More majordomo info at http://vger.kernel.org/majordomo-info.html
