
Chapter 8
Security
8.1 Introduction
This device implements security based on the mode selected from the flash module. The
following sections provide an overview of flash security and details the effects of security
on non-flash modules.
8.2 Flash Security
The flash module provides security information to the MCU based on the state held by
the FSEC[SEC] bits. The MCU, in turn, confirms the security request and limits access to
flash resources. During reset, the flash module initializes the FSEC register using data
read from the security byte of the flash configuration field.
NOTE
The security features apply only to external accesses via debug
and EzPort. CPU accesses to the flash are not affected by the
status of FSEC.
In the unsecured state all flash commands are available to the programming interfaces
(JTAG and EzPort), as well as user code execution of Flash Controller commands. When
the flash is secured (FSEC[SEC] = 00, 01, or 11), programmer interfaces are only
allowed to launch mass erase operations and have no access to memory locations.
Further information regarding the flash security options and enabling/disabling flash
security is available in the
.
K22F Sub-Family Reference Manual, Rev. 4, 08/2016
NXP Semiconductors
195
Summary of Contents for K22F series
Page 2: ...K22F Sub Family Reference Manual Rev 4 08 2016 2 NXP Semiconductors...
Page 168: ...Module clocks K22F Sub Family Reference Manual Rev 4 08 2016 168 NXP Semiconductors...
Page 258: ...Functional description K22F Sub Family Reference Manual Rev 4 08 2016 258 NXP Semiconductors...
Page 292: ...Functional description K22F Sub Family Reference Manual Rev 4 08 2016 292 NXP Semiconductors...
Page 398: ...Functional description K22F Sub Family Reference Manual Rev 4 08 2016 398 NXP Semiconductors...
Page 750: ...Functional description K22F Sub Family Reference Manual Rev 4 08 2016 750 NXP Semiconductors...
Page 816: ...Application information K22F Sub Family Reference Manual Rev 4 08 2016 816 NXP Semiconductors...
Page 890: ...Application information K22F Sub Family Reference Manual Rev 4 08 2016 890 NXP Semiconductors...
Page 1302: ...Application information K22F Sub Family Reference Manual Rev 4 08 2016 1302 NXP Semiconductors...
Page 1374: ...Functional description K22F Sub Family Reference Manual Rev 4 08 2016 1374 NXP Semiconductors...