why the stm32f070c6 entering into DFU mode , when i have connect with usb

[VRajk.1]

Hai,

I am using stm32fo70c6 when i upload the usb_cdc code and connected with usb , it is showing in the device manager as either stm32 DFU mode or stm32 bootloader, it has not detect as a com port, if can anyone knows suggest me , how stm32f070c6 detect as a com port, in some systems it is showing as virtual com port ,some other systems it is showing as either stm32 DFU mode or stm32 bootloader, how can I overcome this error

[TDK · Accepted solution]

Did you write and load firmware that makes it act as a VCP?

It will enter DFU mode if the system bootloader is active and you plug in a USB cable. Perhaps you have BOOT0 held high or floating.

[VRajk.1]

Thanks for your reply @TDK​ , yes, i did write the code and load firmware that works as VCP, how we will inactive the system bootloader , while i uploading the code I'm connecting the boot0 to high , after completion of uploading i have keep the boot0 pin as floating. when i connected to the usb cable it is showing in device manager as stm32 DFU mode/ stm32 bootloader, it didn't detect as a virtual COM port

[TDK]

Boot0 should be held low to run code from flash. Leaving it floating leads to undefined behavior.

[VRajk.1]

Thank you @TDK​  can you clarify my doubt regarding of boot0 pin, when I am uploading code, I am connecting the boot0 pin to high , After completion of code I make it as floating , is it correct procedure or not, is that boot0 pin floating makes the stm32 into DFU mode .

[TDK]

Read my last response. Don't leave BOOT0 floating, ever.

[VRajk.1]

Thanks for your reply @TDK​  I did as per your suggestions , my problem was solved, now it is showing as COM port once again thanks, now I am facing another problem when i want to enable multiple adc channels via polling method ,either all the channels giving same ADC VALUES or wrong adc values( I JUST connected the one of my adc channels to 3.3v pin but it is giving wrong value ), how can I overcome this problem, actually I want to develop multiple adc channel application, the user gives the input data for selection of adc channel through pc via usb COM port , at that time a particular pin is enable and transmit the data, how can i check the conditional receive through usb COM port using usb_cdc_receive function

Thanks and Regards

@VRajk.1​