The MediaTek 2523 series is designed for wearables. It incorporates a Cortex-M4 and an in-package/on-chip QSPI flash.
J-Link debugging support
J-Link supports the MediatTek 2523 series since the following J-Link software versions:
J-Link QSPI support
Unfortunately, the watchdog of the MT2523 series devices keeps running while the core is halted / in debug mode, which makes it impossible to debug the device with watchdog enabled. Therefore, when establishing a debug connection to the device, J-Link disables the watchdog as part of the connect sequence.