On Tue, Apr 16, 2002 at 03:39:27PM +0200, Wolfgang Fritz wrote: > Hello, > > I have a Prolific PL-2303 serial converter connected to my laptop. It > basically works, but I have 3 problems which I am not able to solve: > > 1. After open()-ing the device /dev/ttyUSB0, the first character received on > the serial does not come through.
What do you have the line settings set to? You should use a serial program, not just 'cat' and 'cp' to test these things out. > 2. I can not change the baud rate of the converter. It stays on 9600 Baud. How are you trying to change the baud rate? It seems to work fine for me :) > 3. cp or cat to /dev/ttyUSB0 does not work (hangs forever) Again, see the above comment about not using these programs for testing. I recommend using minicom or any other serial terminal program. See the Linux Serial Programming HOWTO for more info on how to write code to talk to serial ports. > I found this with an application program which bootloads a program to a > 68LC302 microcontroller which has a special serial bootload mode which works > as follows: Is the 68LC302 connected up to the pl2303 device? > 1. Enable serial bootload mode. This switches the serial port on the 68LC302 > to 9600 baud. > > 2. Send exactly 576 bytes bootloader binary code to the 68LC302. These bytes > are stored in an internal RAM and after rececption of the last byte, it is > started. The 68LC302 echoes the received bytes for error checking. Here I > found the "missing first byte" bug. > > 3. The bootloader expects the application program in S-record format with > 115200 Baud. The host switches to 115200 and sends the S-record file with a > cp <file> /dev/ttyUSB0. Here I found the bugs 2 and 3. > > This procedure works without problems with a standard serial port. Try loading the pl2303 driver with "debug=1" so you can see the data and line changes happening on the device. That might help you out to see what is wrong with either your user program, or the driver. > 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. thanks, greg k-h _______________________________________________ [EMAIL PROTECTED] To unsubscribe, use the last form field at: https://lists.sourceforge.net/lists/listinfo/linux-usb-users
