8.3 Security Interactions with other Modules
The flash security settings are used by the SoC to determine what resources are available.
The following sections describe the interactions between modules and the flash security
settings or the impact that the flash security has on non-flash modules.
8.3.1 Security Interactions with EzPort
When flash security is active the MCU can still boot in EzPort mode. The EzPort holds
the flash logic in NVM special mode and thus limits flash operation when flash security
is active. While in EzPort mode and security is active, flash bulk erase (BE) can still be
executed. The write FCCOB registers (WRFCCOB) command is limited to the mass
erase (Erase All Blocks) and verify all 1s (Read 1s All Blocks) commands. Read accesses
to internal memories via the EzPort are blocked when security is enabled.
The mass erase can be used to disable flash security, but all of the flash contents are lost
in the process. A mass erase via the EzPort is allowed even when some memory locations
are protected.
When mass erase has been disabled, mass erase via the EzPort is blocked and cannot be
defeated.
8.3.2 Security Interactions with Debug
When flash security is active the JTAG port cannot access the memory resources of the
MCU. Boundary scan chain operations work, but debugging capabilities are disabled so
that the debug port cannot read flash contents.
Although most debug functions are disabled, the debugger can write to the Flash Mass
Erase in Progress bit in the MDM-AP Control register to trigger a mass erase (Erase All
Blocks) command. A mass erase via the debugger is allowed even when some memory
locations are protected.
When mass erase is disabled, mass erase via the debugger is blocked.
Security Interactions with other Modules
K22F Sub-Family Reference Manual , Rev. 3, 7/2014
192
Freescale Semiconductor, Inc.
Содержание MK22FN256VDC12
Страница 2: ...K22F Sub Family Reference Manual Rev 3 7 2014 2 Freescale Semiconductor Inc...
Страница 136: ...Human machine interfaces K22F Sub Family Reference Manual Rev 3 7 2014 136 Freescale Semiconductor Inc...
Страница 164: ...Module clocks K22F Sub Family Reference Manual Rev 3 7 2014 164 Freescale Semiconductor Inc...
Страница 246: ...Functional description K22F Sub Family Reference Manual Rev 3 7 2014 246 Freescale Semiconductor Inc...
Страница 328: ...Kinetis Flashloader Status Error Codes K22F Sub Family Reference Manual Rev 3 7 2014 328 Freescale Semiconductor Inc...
Страница 360: ...Functional description K22F Sub Family Reference Manual Rev 3 7 2014 360 Freescale Semiconductor Inc...
Страница 388: ...Functional description K22F Sub Family Reference Manual Rev 3 7 2014 388 Freescale Semiconductor Inc...
Страница 402: ...Initialization application information K22F Sub Family Reference Manual Rev 3 7 2014 402 Freescale Semiconductor Inc...
Страница 500: ...Initialization application information K22F Sub Family Reference Manual Rev 3 7 2014 500 Freescale Semiconductor Inc...
Страница 670: ...Flash memory map for EzPort access K22F Sub Family Reference Manual Rev 3 7 2014 670 Freescale Semiconductor Inc...
Страница 680: ...Functional description K22F Sub Family Reference Manual Rev 3 7 2014 680 Freescale Semiconductor Inc...
Страница 744: ...Application information K22F Sub Family Reference Manual Rev 3 7 2014 744 Freescale Semiconductor Inc...
Страница 784: ...Functional description K22F Sub Family Reference Manual Rev 3 7 2014 784 Freescale Semiconductor Inc...
Страница 794: ...Initialization Application Information K22F Sub Family Reference Manual Rev 3 7 2014 794 Freescale Semiconductor Inc...
Страница 960: ...Example configuration for chained timers K22F Sub Family Reference Manual Rev 3 7 2014 960 Freescale Semiconductor Inc...
Страница 1036: ...Device mode IRC48 operation K22F Sub Family Reference Manual Rev 3 7 2014 1036 Freescale Semiconductor Inc...
Страница 1040: ...USB Voltage Regulator Module Signal Descriptions K22F Sub Family Reference Manual Rev 3 7 2014 1040 Freescale Semiconductor Inc...
Страница 1094: ...Initialization application information K22F Sub Family Reference Manual Rev 3 7 2014 1094 Freescale Semiconductor Inc...
Страница 1128: ...Initialization application information K22F Sub Family Reference Manual Rev 3 7 2014 1128 Freescale Semiconductor Inc...
Страница 1216: ...Application information K22F Sub Family Reference Manual Rev 3 7 2014 1216 Freescale Semiconductor Inc...
Страница 1298: ...Functional description K22F Sub Family Reference Manual Rev 3 7 2014 1298 Freescale Semiconductor Inc...
Страница 1312: ...K22F Sub Family Reference Manual Rev 3 7 2014 1312 Freescale Semiconductor Inc...