TM4C1237D5PZ Datasheet, PDF (560/1306 Pages) Texas Instruments – Tiva Microcontroller

Internal Memory
Register 27: EEPROM Debug Mass Erase (EEDBGME), offset 0x080
The EEDBGME register is used to mass erase the EEPROM block back to its default state from
the factory. This register is intended to be used only for debug and test purposes, not in production
environments. The erase takes place in such a way as to be secure. It first erases all data and then
erases the protection mechanism. This register can only be written from supervisor mode by the
core, and can also be written by the TM4C1237D5PZ debug controller when enabled. A key is used
to avoid accidental use of this mechanism. Note that if a power down takes place while erasing, the
mechanism should be used again to complete the operation. Powering off prematurely does not
expose secured data.
To start a mass erase, the whole register must be written as 0xE37B.0001. The register reads back
as 0x1 until the erase is fully completed at which time it reads as 0x0. The EEDONE register is set
to 0x1 when the erase is started and changes to 0x0 or an error when the mass erase is complete.
Note that mass erasing the EEPROM block means that the wear-leveling counters are also reset
to the factory default.
EEPROM Debug Mass Erase (EEDBGME)
Base 0x400A.F000
Offset 0x080
Type RW, reset 0x0000.0000
31
30
29
28
27
26
25
24
23
22
21
20
19
18
17
16
KEY
Type WO
WO
WO
WO
WO
WO
WO
WO
WO
WO
WO
WO
WO
WO
WO
WO
Reset
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
15
14
13
12
11
10
9
8
7
6
5
4
3
2
1
0
reserved
ME
Type RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RO
RW
Reset
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
0
Bit/Field
31:16
15:1
0
Name
KEY
reserved
ME
Type
WO
RO
RW
Reset
0x0000
0x000
0
Description
Erase Key
This field must be written with 0xE37B for the ME field to be effective.
Software should not rely on the value of a reserved bit. To provide
compatibility with future products, the value of a reserved bit should be
preserved across a read-modify-write operation.
Mass Erase
Value Description
0 No action.
1 When written as a 1, the EEPROM is mass erased. This bit
continues to read as 1 until the EEPROM is fully erased.
560
June 12, 2014
Texas Instruments-Production Data