µVISION DEBUGGER: µVision does not Detect Mbed DAPLink

Information in this knowledgebase article applies to:

• Keil MDK Version 5.28 and earlier
• DAPLink versions which are based on CMSIS-DAP V2

SYMPTOM

Keil MDK version 5.28 or before does not detect an Mbed DAPLink debug adapter which is based on CMSIS-DAP V2.

CAUSE

An Mbed DAPLink device is a USB composite device which consists of several USB classes (MSC, CDC, HID, WinUSB). Since CMSIS-DAP V2, a WinUSB bulk transfer is used instead of USB-HID. The µVision CMSIS-DAP debug driver always used the first interface (0) of a USB composite device to communicate. However, new DAPLink releases have the MSC on interface 0 and WinUSB on a higher interface number.

RESOLUTION

Download the attached ZIP file and extract the CMSIS-DAP debug driver file (CMSIS_DAP.dll V0.2.14.1) into the Keil MDK installation folder \ARM\BIN. If the default installation path was used, this is the folder C:\Keil_v5\ARM\BIN

This patch fixes the issues described as 'current limitation #1' for this GitHub commit.

STATUS

This will be fixed in Keil MDK version 5.29 and later.

MORE INFORMATION

• Mbed DAPLink GitHub repository
• Arm CMSIS-DAP repository

ATTACHED FILES

Request the files attached to this knowledgebase article.

Last Reviewed: Friday, January 8, 2021