Section 18.3.3.4, “cfmprot, Cfm protection register, 4 cfmprot — cfm protection register – Freescale Semiconductor ColdFire MCF52210 User Manual

Page 300

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ColdFire Flash Module (CFM)

MCF52211 ColdFire® Integrated Microcontroller Reference Manual, Rev. 2

18-10

Freescale Semiconductor

The CFMSEC register is loaded from the flash configuration field in the flash block at offset 0x0414
during the reset sequence, indicated by F in

Figure 18-6

.

The CFM flash security operation is described in

Section 18.4.3, “Flash Security Operation”

.

18.3.3.4

CFMPROT — CFM Protection Register

The CFMPROT register defines which flash logical sectors are protected against program and erase
operations.

Figure 18-7. CFM Protection Register (CFMPROT)

All CFMPROT register bits are readable and only writable when LOCK=0.

The flash memory is divided into logical sectors for the purpose of data protection using the CFMPROT
register. The flash memory consists of 32 4kByte sectors as shown in <f-helvetica><st-bold>Figure 18-8..

29-16

Reserved, should read 0

15 - 0

SEC

Flash memory security bits
The SEC bits define the security state of the MCU as shown in

Table 18-7

, which defines the single code

that enables the security feature in the CFM

Table 18-7. CFM Security States

SEC[15:0]

Description

0x4AC8

1

1

This value was chosen because it represents the ColdFire HALT instruction, making
it unlikely that a user compiled code accidentally programmed at the security
configuration field location would unintentionally secure the flash memory.

Flash Memory Secured

All other combinations

Flash Memory Unsecured

IPSBAR

Offset: 0x1D_0010 (CFMPROT)

Access: User read/write

31

30

29

28

27

26

25

24

23

22

21

20

19

18

17

16

R

PROTECT

W

Reset

F

1

1

Reset state loaded from flash configuration field during reset.

F

1

F

1

F

1

F

1

F

1

F

1

F

1

F

1

F

1

F

1

F

1

F

1

F

1

F

1

F

1

15

14

13

12

11

10

9

8

7

6

5

4

3

2

1

0

R

PROTECT

W

Reset

F

1

F

1

F

1

F

1

F

1

F

1

F

1

F

1

F

1

F

1

F

1

F

1

F

1

F

1

F

1

F

1

Table 18-6. CFMSEC Field Descriptions

Field

Description

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