SEGGER’s latest J-Link software makes it possible to turn J-Link into a high-speed CMSIS-DAP debug probe. In this mode, it can be used with any toolchain or application that is compatible with this standard, such as pyOCD, KEIL MDK, and Arms Development Studio.
This mode is available for J-Link BASE, J-Link PLUS, J-Link EDU, J-Link ULTRA+, and J-Link PRO. These intelligent debug probes use a 480 Mbps high-speed USB connection to eliminate idle periods and drive the target interface at its full speed, up to 50 MHz on J-Link ULTRA+ and PRO.
Switching to CMSIS-DAP mode and back to J-Link is easily done via J-Link Configurator. While J-Link gets the most out of CMSIS-DAP, J-Link’s full performance, functionality, and feature set require J-Link mode.