The device has two watchdogs SWDT and HWDT that are fed during flash programming.
Device Specific Handling
Reset
The device uses normal Cortex-M reset, no special handling necessary, like described here.
Security code
The security code 0x0001 can be programmed at address 0x00100000 to activate the locking mechanism. If the device is locked, debugging features are disabled. To unlock the device, a mass erase operation must be performed using the serial port programming application provided by the silicon vendor.