TM4C1231E6PM_15 Datasheet, PDF (499/1145 Pages) Texas Instruments – Tiva™ TM4C1231E6PM Microcontroller

Tiva^™ TM4C1231E6PM Microcontroller
8.2.4
8.2.4.1
Table 8-2. User-Programmable Flash Memory Resident Registers (continued)
Register to be Committed
BOOTCFG
FMA Value
0x7510.0000
Data Source
FMD
EEPROM
The TM4C1231E6PM microcontroller includes an EEPROM with the following features:
■ 2Kbytes of memory accessible as 512 32-bit words
■ 32 blocks of 16 words (64 bytes) each
■ Built-in wear leveling
■ Access protection per block
■ Lock protection option for the whole peripheral as well as per block using 32-bit to 96-bit unlock
codes (application selectable)
■ Interrupt support for write completion to avoid polling
■ Endurance of 500K writes (when writing at fixed offset in every alternate page in circular fashion)
to 15M operations (when cycling through two pages ) per each 2-page block.
Functional Description
The EEPROM module provides a well-defined register interface to support accesses to the EEPROM
with both a random access style of read and write as well as a rolling or sequential access scheme.
A protection mechanism allows locking EEPROM blocks to prevent writes under a set of
circumstances as well as reads under the same or different circumstances. The password model
allows the application to lock one or more EEPROM blocks to control access on 16-word boundaries.
Important: The configuration of the system clock must not be changed while an EEPROM operation
is in process. Software must wait until the WORKING bit in the EEPROM Done Status
(EEDONE) register is clear before making any changes to the system clock.
Blocks
There are 32 blocks of 16 words each in the EEPROM. Bytes and half-words can be read, and
these accesses do not have to occur on a word boundary. The entire word is read and any unneeded
data is simply ignored. They are writable only on a word basis. To write a byte, it is necessary to
read the word value, modify the appropriate byte, and write the word back.
Each block is addressable as an offset within the EEPROM, using a block select register. Each
word is offset addressable within the selected block.
The current block is selected by the EEPROM Current Block (EEBLOCK) register. The current
offset is selected and checked for validity by the EEPROM Current Offset (EEOFFSET) register.
The application may write the EEOFFSET register any time, and it is also automatically incremented
when the EEPROM Read-Write with Increment (EERDWRINC) register is accessed. However,
the EERDWRINC register does not increment the block number, but instead wraps within the block.
Blocks are individually protectable. Attempts to read from a block for which the application does not
have permission return 0xFFFF.FFFF. Attempts to write into a block for which the application does
not have permission results in an error in the EEDONE register.
June 12, 2014
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Texas Instruments-Production Data