PC312XDP512F0CFVR datasheet(1113/1348 Pages) FREESCALE

1113 / 1348 page

Chapter 27 512 Kbyte Flash Module (S12XFTX512K4V2)

MC9S12XDP512 Data Sheet, Rev. 2.21

Freescale Semiconductor

1115

All bits in the FSEC register are readable but are not writable.

The FSEC register is loaded from the Flash Conﬁguration Field at address 0x7F_FF0F during the reset

sequence, indicated by F in Figure 27-5.

The security function in the Flash module is described in Section 27.6, “Flash Module Security”.

27.3.2.3

Flash Test Mode Register (FTSTMOD)

The FTSTMOD register is used to control Flash test features.

76543210

KEYEN

RNV5

RNV4

RNV3

RNV2

SEC

Reset

FFFFF

= Unimplemented or Reserved

Figure 27-5. Flash Security Register (FSEC)

Table 27-4. FSEC Field Descriptions

Field

Description

7-6

KEYEN[1:0]

Backdoor Key Security Enable Bits — The KEYEN[1:0] bits deﬁne the enabling of backdoor key access to the

Flash module as shown in Table 27-5.

5-2

RNV[5:2]

Reserved Nonvolatile Bits — The RNV[5:2] bits should remain in the erased state for future enhancements.

1-0

SEC[1:0]

Flash Security Bits — The SEC[1:0] bits deﬁne the security state of the MCU as shown in Table 27-6. If the

Flash module is unsecured using backdoor key access, the SEC[1:0] bits are forced to 1:0.

Table 27-5. Flash KEYEN States

KEYEN[1:0]

Status of Backdoor Key Access

DISABLED

011

1 Preferred KEYEN state to disable Backdoor Key Access.

DISABLED

ENABLED

DISABLED

Table 27-6. Flash Security States

SEC[1:0]

Status of Security

SECURED

011

1 Preferred SEC state to set MCU to secured state.

SECURED

UNSECURED

SECURED

PC312XDP512F0CFVR Datasheet(PDF) 1113 Page - Freescale Semiconductor, Inc

PC312XDP512F0CFVR Datasheet(HTML) 1113 Page - Freescale Semiconductor, Inc

Html Pages

1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 51 52 53 54 55 56 57 58 59 60 61 62 63 64 65 66 67 68 69 70 71 72 73 74 75 76 77 78 79 80 81 82 83 84 85 86 87 88 89 90 91 92 93 94 95 96 97 98 99 100 ...More

Datasheet Download

Link URL