LM3S5956-IQR80-C1 Datasheet, PDF (351/1144 Pages) Texas Instruments – Stellaris® LM3S5956 Microcontroller

NRND: Not recommended for new designs.
Stellaris^® LM3S5956 Microcontroller
Register 23: Flash Memory Protection Program Enable 2 (FMPPE2), offset
0x408
Note: Offset is relative to System Control base address of 0x400FE000.
This register stores the execute-only protection bits for each 2-KB flash block (FMPREn stores the
execute-only bits). Flash memory up to a total of 64 KB is controlled by this register. Other FMPPEn
registers (if any) provide protection for other 64K blocks. This register is loaded during the power-on
reset sequence. The factory settings for the FMPREn and FMPPEn registers are a value of 1 for
all implemented banks. This achieves a policy of open access and programmability. The register
bits may be changed by writing the specific register bit. However, this register is R/W0; the user can
only change the protection bit from a 1 to a 0 (and may NOT change a 0 to a 1). The changes are
not permanent until the register is committed (saved), at which point the bit change is permanent.
If a bit is changed from a 1 to a 0 and not committed, it may be restored by executing a power-on
reset sequence. The reset value shown only applies to power-on reset; any other type of reset does
not affect this register. Once committed, the only way to restore the factory default value of this
register is to perform the sequence detailed in “Recovering a "Locked" Microcontroller” on page 182.
If the Flash memory size on the device is less than 128 KB, this register usually reads as zeroes,
but software should not rely on these bits to be zero. For additional information, see “Flash Memory
Protection” on page 320.
Flash Memory Protection Program Enable 2 (FMPPE2)
Base 0x400F.E000
Offset 0x408
Type R/W, reset 0xFFFF.FFFF
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
PROG_ENABLE
Type R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
Reset
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
PROG_ENABLE
Type R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
R/W
Reset
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
1
Bit/Field
31:0
Name
PROG_ENABLE
Type
Reset Description
R/W 0xFFFFFFFF Flash Programming Enable
Configures 2-KB flash blocks to be execute only. The policies may be
combined as shown in Table 7-1 on page 320.
Value
Description
0xFFFFFFFF Bits [31:0] each enable protection on a 2-KB block of
Flash memory in the range from 129 to 192 KB.
October 06, 2012
351
Texas Instruments-Production Data