April 2007 - WLUG - wlug.mailman3.com

Re: [Wlug] Seeking help with a USB barcode scanner

by Jamie Guinan

On Mon, 2 Apr 2007, Andy Stewart wrote: > -----BEGIN PGP SIGNED MESSAGE----- > Hash: SHA1 > > Tim Keller wrote: > > This is what I would do. > > > > 1. Install "lsusb". It behaves much like lspci so you can what devices > > are on your system. > > > > When you do a "lsusb" it'll list what devices are hanging off of each > > USB bus. Do a before and after so you can see the major/minor numbers. > > > > 2. When you know the devices major and minor number you can write a > > program using libusb that'll look for the device, open the device if it > > exists, take posession of it and then read data to and from it, hopefully. > > http://libusb.sourceforge.net/doc/examples-code.html > > > > Looking at that example, I don't think it would be too hard to whip up a > > program to open the device and then loop until there's input and then > > dump it on the screen. > > > > Thanks, > > Tim. > > HI Tim, > > Thanks for the tip about libusb. I have lsusb installed, and I also > have usbview. > > I'm surprised that I can't find the proper thing to "cat" to see output > from the barcode reader. That would be the shell equivalent of what you > propose. If I could find that, I'd be in business. I'm 99% certain > that I'm looking in the right place. Now, I wonder if it is possible > that the barcode reader is defective.......hummmmm. > > Once I find the right file to "cat", whipping up a program to grab the > bytes and deal with them would be fairly trivial, I agree. > > Thanks! > > Andy It might be that the device needs some initialization before it will start returning data. I wouldn't expect this for a HID device, but since the event* nodes aren't showing anything, who knows... In the kernel, it would be interesting to see what happens if you turn on DEBUG in hid-input.c, which currently contains, #undef DEBUG ... static void hidinput_configure_usage() ... goto ignore; // lots of these gotos! -jamieg ... ignore: #ifdef DEBUG printk("IGNORED\n"); #endif -Jamie

April 3, 2007

New Paging System Makes Scrolling Obsolete

by Bruce Linnell

http://www.dorks.com/videos/books.html

April 3, 2007

Re: [Wlug] Seeking help with a USB barcode scanner

by Andy Stewart

-----BEGIN PGP SIGNED MESSAGE----- Hash: SHA1 Tim Keller wrote: > This is what I would do. > > 1. Install "lsusb". It behaves much like lspci so you can what devices > are on your system. > > When you do a "lsusb" it'll list what devices are hanging off of each > USB bus. Do a before and after so you can see the major/minor numbers. > > 2. When you know the devices major and minor number you can write a > program using libusb that'll look for the device, open the device if it > exists, take posession of it and then read data to and from it, hopefully. > http://libusb.sourceforge.net/doc/examples-code.html > > Looking at that example, I don't think it would be too hard to whip up a > program to open the device and then loop until there's input and then > dump it on the screen. > > Thanks, > Tim. HI Tim, Thanks for the tip about libusb. I have lsusb installed, and I also have usbview. I'm surprised that I can't find the proper thing to "cat" to see output from the barcode reader. That would be the shell equivalent of what you propose. If I could find that, I'd be in business. I'm 99% certain that I'm looking in the right place. Now, I wonder if it is possible that the barcode reader is defective.......hummmmm. Once I find the right file to "cat", whipping up a program to grab the bytes and deal with them would be fairly trivial, I agree. Thanks! Andy - -- Andy Stewart, Founder Worcester Linux Users' Group (http://www.wlug.org) Chelmsford Linux Meetup Group (http://linux.meetup.com/393) Amateur Radio: KB1OIQ -----BEGIN PGP SIGNATURE----- Version: GnuPG v1.4.2 (GNU/Linux) Comment: Using GnuPG with SUSE - http://enigmail.mozdev.org iD8DBQFGEX21Hl0iXDssISsRAhhCAJ9Y4iidL2WKRRyAqMFz06c1Nbd7yQCffu6p 2XTWxxQuiKaj27rVAGw9HxY= =Q0Ie -----END PGP SIGNATURE-----

April 2, 2007

Re: [Wlug] Seeking help with a USB barcode scanner

by Tim Keller

This is what I would do. 1. Install "lsusb". It behaves much like lspci so you can what devices are on your system. When you do a "lsusb" it'll list what devices are hanging off of each USB bus. Do a before and after so you can see the major/minor numbers. 2. When you know the devices major and minor number you can write a program using libusb that'll look for the device, open the device if it exists, take posession of it and then read data to and from it, hopefully. http://libusb.sourceforge.net/doc/examples-code.html Looking at that example, I don't think it would be too hard to whip up a program to open the device and then loop until there's input and then dump it on the screen. Thanks, Tim. On 3/31/07, Keith Wright <kwright(a)keithdiane.us> wrote: > > > From: Jamie Guinan <guinan(a)bluebutton.com> > > > > > > I tried your "od -x" trick on each of these to no avail. I > > > pointed the barcode scanner at some arbitrary barcodes, and it > > > beeped and turned off the red light, but nothing appeared on my > > > screen as a result of the "od -x". > > > > > > Are there other possibilities to consider? > > > > At this point I'd start putting printk's and turning on DEBUGs in > > the kernel source. For starters, > > If you get to the point of modifying the kernel source, > can you be far from wanting an oscilloscope on the pins? > > -- Keith > _______________________________________________ > Wlug mailing list > Wlug(a)mail.wlug.org > http://mail.wlug.org/mailman/listinfo/wlug > -- I am leary of the allegiances of any politician who refers to their constituents as "consumers".

April 2, 2007