Question about virtual com port

[Jyoti Bhayana]

I have a technical issue I am facing while doing development with Nordic NRF52840. I have an application which I am sending command though virtual com port using CDC ACM USB class. When the application is running the COM port shows as Port 30 on my windows. When I switch to my bootloader which also uses virtual com port using CDC ACM USB class, the port changes to 29 . Why the port is not remaining the same in both app and bootloader mode. Is there a way that the port number remains the same when I switch from my application to my bootloader application

In my sdk_config.h file I have same vendor and product ID. // Vendor ID ordered from USB IF: www.usb.org/.../ #ifndef APP_USBD_VID #define APP_USBD_VID 0x1915 #endif

// APP_USBD_PID - Product ID

// Selected Product ID #ifndef APP_USBD_PID #define APP_USBD_PID 0x520F #endif

[Sigurd]

Hi,

Are you always using the nRF USB port, or are you also using the Segger J-Link USB port?

Also please provide some more information.

• What SDK version are you using?
• What version of the nRF52840 PDK are you using? It should be printed below PCA10056 on the sticker on the kit.
• Do you have more than 1 nRF52840-PDK you can test with?
• Do you have custom boards using "engineer samples" ?

If you are using engineer samples:

• How many of these custom boards with engineer samples do you have ?
• What is the build code on the engineer samples?