EEPROM Registers
582
SLAU723A – October 2017 – Revised October 2018
Copyright © 2017–2018, Texas Instruments Incorporated
Internal Memory
7.4.10 EEPASS0 to EEPASS2 Registers (Offset = 0x34 to 0x3C) [reset = X]
EEPROM Password (EEPASS0), offset 0x034
EEPROM Password (EEPASS1), offset 0x038
EEPROM Password (EEPASS2), offset 0x03C
The EEPASSn registers are used to configure a password for a block. A password may only be set once
and cannot be changed. The password may be 32-bits, 64-bits, or 96-bits. Each word of the password can
be any 32-bit value other than 0xFFFFFFFF (all 1s). To set a password, the EEPASS0 register is written
to with a value other than 0xFFFFFFFF. When the write completes, as indicated in the EEDONE register,
the application may choose to write to the EEPASS1 register with a value other than 0xFFFFFFFF. When
that write completes, the application may choose to write to the
EEPASS2
register with a value other than
0xFFFFFFFF to create a 96-bit password. The registers do not have to be written consecutively, and the
EEPASS1 and EEPASS2 registers may be written at a later date. Based on whether 1, 2, or all 3 registers
have been written, the unlock code also requires the same number of words to unlock.
NOTE:
Once the password is written, the block is not actually locked until either a reset occurs or
0xFFFFFFFF is written to EEUNLOCK.
NOTE:
A read of the EEPASSn register during the EEPROM initialization sequence is only valid
when the WORKING bit is 0 in EEDONE register:
EEPASSn is shown in
and described in
Return to
Figure 7-34. EEPASS0 to EEPASS2 Registers
31 30 29 28 27 26 25 24 23 22 21 20 19 18 17 16 15 14 13 12 11 10
9
8
7
6
5
4
3
2
1
0
PASS
R/W-X
Table 7-35. EEPASS0 to EEPASS2 Registers Field Descriptions
Bit
Field
Type
Reset
Description
31-0
PASS
R/W
X
Password
This register reads as 0x1 if a password is registered for this block
and 0x0 if no password is registered.
A write to this register if it reads as 0x0 sets the password.
If an attempt is made to write to this register when it reads as 0x1,
the write is ignored and the NOPERM bit in the EEDONE register is
set.