USB-Serial FTDI error

[zenzen]

Hello

   I have a problem about usb to serial device. I buy sheevaplug with Ubuntu and Debian sd-card. I use USB-HUB to connect 3 devices that are usb-serial devices. I use Ubuntu sd-card. When I connect 3 usb-serial devices It will create /dev/ttyUSBX(X = 0,1,2) automatically. I can use 1 device at a time. But When I use 3 devices in 1 program. I found the error

ftdi_sio ttyUSB0: ftdi_set_termios FAILED to set databits/stopbits/parity
ftdi_sio ttyUSB0: ftdi_set_termios urb failed to set baudrate
ftdi_sio ttyUSB0: urb failed to clear flow control
   
   What is the probable cause ? Can Anyone help me ?

Thanks in advance


zenzen

[NewIT_Marcus]

Hello

   I have a problem about usb to serial device. I buy sheevaplug with Ubuntu and Debian sd-card. I use USB-HUB to connect 3 devices that are usb-serial devices. I use Ubuntu sd-card. When I connect 3 usb-serial devices It will create /dev/ttyUSBX(X = 0,1,2) automatically. I can use 1 device at a time. But When I use 3 devices in 1 program. I found the error

ftdi_sio ttyUSB0: ftdi_set_termios FAILED to set databits/stopbits/parity
ftdi_sio ttyUSB0: ftdi_set_termios urb failed to set baudrate
ftdi_sio ttyUSB0: urb failed to clear flow control
   
   What is the probable cause ? Can Anyone help me ?

You are connecting a Sheevaplug to a 3 (or more) port hub, and from there you are connecting to 3 more serial devices, is that correct?

And are you using an Ubuntu or a Debian SD card?

The closest information that I could find that seems relevant is here.

[zenzen]

Thanks for your help

-You are connecting a Sheevaplug to a 3 (or more) port hub, and from there you are connecting to 3 more serial devices, is that correct?
  Correct 

-And are you using an Ubuntu or a Debian SD card?
   Both, On Ubuntu, Devices file created automatically. On Debian I create device files by using mknod command.

-The closest information that I could find that seems relevant is here.
   I already read that link but still don't understand.

I don't sure The problem is about mix of speed of devices on USB-HUB.
May you ask me for additional information ?

Thanks

   

[NewIT_Marcus]

Thanks for your help

-You are connecting a Sheevaplug to a 3 (or more) port hub, and from there you are connecting to 3 more serial devices, is that correct?
  Correct 

-And are you using an Ubuntu or a Debian SD card?
   Both, On Ubuntu, Devices file created automatically. On Debian I create device files by using mknod command.

But it works on Debian, but not Ubuntu? or it fails on both?

-The closest information that I could find that seems relevant is here.
   I already read that link but still don't understand.

I don't sure The problem is about mix of speed of devices on USB-HUB.
May you ask me for additional information ?

I know very little about the issue you raise. But I am aware that there is a difference in how Ubuntu and Debian create the device files in /dev. You seem to be aware of that too, so I don't know that I can help.

[zenzen]

it fails on both. The error is the same that is

ftdi_sio ttyUSB0: ftdi_set_termios FAILED to set databits/stopbits/parity
ftdi_sio ttyUSB0: ftdi_set_termios urb failed to set baudrate
ftdi_sio ttyUSB0: urb failed to clear flow control

[Baz]

Going back a step can anyone recommend a USB to Serial device and explain using it on a plain plug in plain English. Drivers?
I see several products mentioning their included disc of windowsxyz drivers but only one mentions Linux and is 3 times the price.
I too wish to end up with about 3 and talking to a perl program.

[apemberton]

What is the output from the command 'lsusb'?

That should show the PID/VID of all USB attached devices. There is some confusion about the VID/PID for fdti chips as current fdti supplied drivers use 0x403/0x6010 but I have a sheevaplug that uses 0x9e88/0x9e8f. I understand the change occurred about Q4 of 2009.

The upshot was that I had to modify my fdti/Vista64 driver '.inf' files to reflect the older values. My linux system (using both ttyUSB0 and OpenOCD 'sheevaplug.cfg' file) had the correct values for my sheevaplug. Linux is easy to change compared with Vista64!

This might be a red herring of course.