The PSWDLOCK feature is required to protect the user's CSM passwords before a device is released for production. The JTAGLOCK feature prevents unauthorized JTAG access of any kind to the device. EXEONLY protection blocks all data reads or writes to a specific memory region. CRCLOCK blocks the VCRC module from calculating CRCs on secure resources. The CMACKEY settings and secure flash boot feature ensure the application code in flash has not been tampered with before execution.