USB CDC Virtual COM Port Device

M

mwpau

Greetings all,

First up, i'm super new to FreeBSD, so please go easy on me.
(i'm rather familiar with Linux though)

I have a STM32 microcontroller based USB device that presents itself as a CDC VCP device.
I'm using ST's USB CDC device library.

On attaching the device i see in the kernel log:
Code: 
ugen0.2: <STMicroelectronics STM32 Virtual ComPort> at usbus0
umodem0 on uhub1
umodem0: <STMicroelectronics STM32 Virtual ComPort, class 2/2, rev2.00/2.00, addr2> on usbus0
umodem0: data interface 1, has no CM over data, has no break

On trying to use the VCP at /dev/cuaU0, data flows as it should for a random amount of time, and then fails.
The device works perfectly with both Windows and Linux, so this does appear to be a FreeBSD driver issue.

Does anyone has any advice on how I should go about solving this issue?

Thanks in advance!
 
mwpau said:
On trying to use the VCP at /dev/cuaU0, data flows as it should for a random amount of time, and then fails.
Click to expand...
Fails how? Does it time-out? Or stop responding? Did you check things like flowcontrol (RTS/CTS, Xon/Xoff)?
 
I've been testing in a VirtualBox VM... which now i think about it isn't the best idea.
I'll setup a PC and try again.
I'm pretty confident it'll still have issues, but at least i'll be able to rule out the VM.
 
mwpau said:
I've been testing in a VirtualBox VM... which now i think about it isn't the best idea.
I'll setup a PC and try again.
I'm pretty confident it'll still have issues, but at least i'll be able to rule out the VM.
Click to expand...
Yeah, I'm not that confident about USB pass-through. Definitely try this on "real" hardware.
 
Hello ... so ... this error does take place on live systems.

how to reproduce:
You need STM32F103, STM32F407, or any STM32 with USB support.
Code : easiest way to use auto generated by Cube MX - USB CDC Device.
then - all you need is plug your newly flashed board to FreeBSD machine in DMesg message will appear:
umodem0: data interface 1, has no CM over data, has no break

here is usbconfig output:
Code: 
usbconfig -d ugen0.4 dump_device_desc
ugen0.4: <DevEL DevEL-HWCodec-DEV> at usbus0, cfg=0 md=HOST spd=FULL (12Mbps) pwr=ON (100mA)

  bLength = 0x0012
  bDescriptorType = 0x0001
  bcdUSB = 0x0200
  bDeviceClass = 0x0002  <Communication device>
  bDeviceSubClass = 0x0000
  bDeviceProtocol = 0x0000
  bMaxPacketSize0 = 0x0040
  idVendor = 0x03eb
  idProduct = 0x6133
  bcdDevice = 0x0200
  iManufacturer = 0x0001  <DevEL>
  iProduct = 0x0002  <DevEL-HWCodec-DEV>
  iSerialNumber = 0x0003  <00000000001A>
  bNumConfigurations = 0x0001

This USB CDC Device working on linux flawlessly. you get /dev/ttyACMx on linux.
 
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