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STM32CubeProgrammer 2.16.0 DFU Bootloader Error

Associate II

I am using CubeProgrammer_API to implement a firmware update on my app. I am encountering an error where it cannot connect to the DFU bootloader. The device is visible in device manager and it is properly connected.

int usbConnectFlag = connectDfuBootloader(dfuList[0].usbIndex);
This line is causing me issues as it is not printing any values. Any code below this line would not run. I am not sure what is the issue.
ST Employee

Hello @i124q,

First of all are you able to connect via CubeProgrammer GUI ? And could you please specify the device you're using ? If you're using a custom DFU application (Not STM32 bootloader), could you please attach the binary ?

Thanks in advance,


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Associate II

I have a similar error with the STM32CubeProgrammer Application.

If I install the STM32CubeProgrammer version 2.15, the download to my DFU bootloader works without any problems.
If I install the STM32CubeProgrammer version 2.16, the running bootloader is recognized. If you then press the "Connect" button, the CubeProgrammer tries to establish a connection, but cannot. The connect button remains grayed out and the connection status remains “not connected”.
The Log from the output window shows the following:

16:30:22 : STM32CubeProgrammer API v2.16.0 | Windows-64Bits
16:30:40 : UR connection mode is defined with the HWrst reset mode
16:30:40 : USB speed : Full Speed (12MBit/s)
16:30:40 : Manuf. ID : Company Name
16:30:40 : Product ID : NG96 Firmware Update
16:30:40 : SN : 204D36813430
16:30:40 : DFU protocol: 1.1
16:30:40 : Board : --
16:30:40 : IAP

If I go back to the Version 2.15 everythings runs fine.
Do I need to change something on my Bootloader, when I use STM32CubeProgrammer v2.16 instead of v2.15?

It looks like the initial problem from "i124q".