TM4C123GH6PM: Change USB description in device manager?

Hello Steve

No, that cannot be changed as the description comes from the driver. Since all of them use the same driver the display will remain the same. The only way an application can distinguish the same, is by means of the querying the device descriptors and then using the same as per the user requirement.

Does this mean that all customer Tiva based products that use the virtual com port would need their own specific driver (if different description strings are needed)?

What tools do we have available to help customers with modifying the drivers since I would expect this is a fairly common requirement? Even our own 'products' e.g. XDS110 expose virtual com ports but with different description strings (which I would expect use at least some of the same driver code).

I thought that the virtual com port was a MSFT supplied driver that any compliant hardware could utilize (for compatibility)?

BR,

Steve

Hello Steve

The driver is coming from the MSFT supplied driver. In case of XDS110 which is a composite device, the PC reads in the user supplied driver. The different description strings that you are mentioning does not cause them to named separately. The COM port assignment is from the PC for the user to know which COM port is available for use.

OK, if MSFT supplied then where does the descriptor string "TivaWare USB serial port" get pulled from?

Basically, what would customers need to do to get their own descriptions displayed when using Tivaware VCOM? I would not expect them to have to actually write a complete customer driver.

Thanks for your help :)

BR,
Steve

Hello Steve

Apologies for the confusion. That description comes from the usb_dev_serial.inf/cat file. That cannot be changed as all the devices connecting to it would always try to use the registered drivers on the PC.

OK, so the question is still the same then... What would a customer need to do to change the description? Would it require a unique VID/PID? would it necessitate actually writing a new driver? If so, do we have any references to help guide through that process?

BR,
Steve

Hello Steve

Why can't the customer provide a unique Device Serial Number String per device and when calling it from the Windows Application identify the same using the serial number instead of having to use up VID:PID?

Well, one concern is the appearance of being a 'real' product rather than a demo.

Not changing the description string to something more 'professional' than "TivaWare USB serial port" just looks unfinished.

Additionally there does not need to be specific PC side software. Terminal windows can be used to talk to the Tiva's so knowing what commands each Tiva can accept is important. One of the Tiva's will be running firmware that is not under our control so there is no guarantee it will behave 'nicely' if it gets something it doesn't understand.

The bottom line is this... Surely we have customers using TivaWare VCOM ports with their own description. What needs to be done to achieve this?

BR,
Steve

Hello Steve

Let me give an analogy. If one plugs in two mouse devices from the same manufacturer, they would appear with the same device description.

The description string can be changed by editing the INF file and resigning the same. However the naming terminology was something that was meant to be simple

I get that, but what if 2 completely different manufacturers use TivaWare for their products and both are plugged in?

How would an end user be able to determine which one was the 'pool controller' and which one was the 'home heating' controller?

Hello Steve

They would be using different VID:PID as mandated by USB.org

Even if they are using the VCOM interface (through Tivaware)? I thought part of the rationale for Tivaware was to eliminate the need for customer specific VID/PID (or is the limitation of this that the description cannot be changed)?

OK, so the question is still the same then... What would a customer need to do to change the description? Would it require a unique VID/PID (seems like 'yes')? Would it necessitate actually writing a new driver (Would hope 'no', possibly just .inf changes)? If so, do we have any references to help guide through that process?

BR,
Steve

Hello Steve

In that case using VID:PID would be the only logical choice and then they would have to individual drivers for each of them. We do not have any documentation on it as it never has been the case. What I do know from the E2E and customer interactions, is that customers have applications that query the device descriptor and use the serial number of the same to identify each of the devices: Which is the logical method on USB.