On Wed, Apr 17, 2002 at 08:53:49AM +0200, Wolfgang Fritz wrote: > > Done. See attached logs.
Nicly commented, I wish everyone would do this... > > > I did some strace-ing and debugging which gave me error messages about > > > unsupported ioctls in the pl2303 module. If useful, I will post it here. > > > I also looked at the pl2303 source code and found that it has not changed > > > significantly up to 2.5. > > > > There are loads of serial ioctls that are not supported by some of the > > usb-serial drivers, but these can usually be ignored just fine. > > >From the logs I see the following: > > 1. cp, cat, echo to /dev/ttyUSB0 hang in an infinite loop, trying to send > zero length data blocks. For me that looks like a bug, maybe not in the > pl2303 module, but somewhere in the higher layers. I haven't had the best luck using cp, cat, and echo to test out the usb-serial drivers in the past. Small C programs or Perl scripts using the serial port work just fine. Since this is what really matters, I haven't spent any time looking into this issue. > 2. On an open(), the baudrate is reset to 9600. This is intentional (I looked > at pl2303.c), but different from standard serial ports and makes settings via > command line tools like stty useless. For me that's a bug. I'll try to patch > the pl2302.c not to do this reset (or to remember the last settings and reset > to these), but I cannot do that in the office. > > I tried to change the baudrate inside minicom, that works (/dev/ttyUSB0 stays > open) Yes, you are correct, I don't know why the driver is doing that (holdover from the original author :) Patches gladly accepted to fix this problem. > I have to check the "lost first received byte" problem, but that takes a > little longer. If I can resolve or work around this problem, I can change my > download procedure to replace the stty and cp commands by a small program > which keeps the device open between setting the baudrate and transferring the > s-record file. Can you use minicom to send your data, or some other terminal program (I think kermit is highly scriptable)? This might solve all of your problems with using cp and cat. thanks, greg k-h _______________________________________________ [EMAIL PROTECTED] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-users
