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vehemens
03-02-2015, 01:05 AM
I'm after the DARwIn-OP CM730 sub-controller USB descriptor information. In particular the output from the linux command "lsusb -s XXX:YYY -v" where XXX:YYY are the bus and device numbers.

So if anyone with a CM730 could post the information, I would appreciate it.

tician
03-02-2015, 03:01 AM
It uses the ever so common FT232RL, so will be the same as Xbee/FTDI USB2UART dongles and older Arduinos (pre-ATmega8/16U2 boards).

vehemens
03-03-2015, 12:25 AM
It uses the ever so common FT232RL, so will be the same as Xbee/FTDI USB2UART dongles and older Arduinos (pre-ATmega8/16U2 boards).

That helps a lot. Had a quick look at the FT232RL datasheet as well the linux driver and library code. Given how the part works, the actual descriptor information isn't all that useful for what I'm doing, but it would be nice to have for reference as ROBOTIS could of changed some of the configurable parameters.

tician
03-03-2015, 01:02 AM
That helps a lot. Had a quick look at the FT232RL datasheet as well the linux driver and library code. Given how the part works, the actual descriptor information isn't all that useful for what I'm doing, but it would be nice to have for reference as ROBOTIS could of changed some of the configurable parameters.

Very much doubt that Robotis bothered to change anything at all with regard to the FT232RL given they were too cheap/lazy to program each STM32 in the OpenCM-904(A/B) with a unique ID in the USB properties. Fortunately, all FT232RL are programmed with a unique iSerial value during manufacture by FTDI that can be used in udev rules.



edit: And I forgot about the CM-530 which also has an FT232RL that I do not recall having any modifications.

vehemens
03-04-2015, 08:49 PM
Very much doubt that Robotis bothered to change anything at all with regard to the FT232RL given they were too cheap/lazy to program each STM32 in the OpenCM-904(A/B) with a unique ID in the USB properties. Fortunately, all FT232RL are programmed with a unique iSerial value during manufacture by FTDI that can be used in udev rules.



edit: And I forgot about the CM-530 which also has an FT232RL that I do not recall having any modifications.

The only ROBOTIS USB product I have currently have is a bricked usb2dynamixel, however the descriptor information matches a recently purchased FT232RL otherwise.

On the issue of a unique ID for the OpenCM-904, it appears that the capability is there as the STM UM0424 document for the USB-FS-Device firmware library: section 3.4.1 includes the statement "The default value of the serial number string descriptor is “STM32” and during the USBinitialization the Get_SerialNum() function reads the Device Unique ID register and sets the serial number string descriptor."