RM0367 Rev 7 85/1043
RM0367 Flash program memory and data EEPROM (FLASH)
122
Detailed description of NVM write/erase operations
This section details the different types of write and erase operations, showing the necessary
bits for each one.
Write to data EEPROM
• Purpose
Write one word in the data EEPROM with a specific value.
• Size
Write by byte, half-word or word.
• Address
Select a valid address in the data EEPROM.
• Protocol
Single programming operation.
• Requests
PELOCK = 0, ERASE = 0.
• Errors
WRPERR is set to 1 (and the write operation is not executed) if PELOCK = 1 or if the
memory is read-out protected.
• Description
This operation aims at writing a word or a part of a word in the data EEPROM. The user
must write the right value at the right address and with the right size. The memory
interface automatically executes an erase operation when necessary (if all bits are
currently set to 0, there is no need to delete the old content before writing). Similarly, if
the data to write is at 0, only the erase operation is executed. When only a write
operation or an erase operation is executed, the duration is Tprog (3.2 ms); if both are
executed, the duration is 2 x Tprog (6.4 ms). It is possible to force the memory interface
to execute every time both erase and write operations set the FIX flag to 1.
• Duration
Tprog (3.2 ms) or 2 x Tprog (6.4 ms).
• Options
Set the FIX bit to force the memory interface to execute every time an erase (to delete
the old content) and a write operation (to write new data) occur. This gives a fix time for
the operation for any data value and for previous data.
• Erase/write endurance cycles in data EEPROM are linked to one single word
granularity (one erase/write cycle degrades only one programmed word area in data
EEPROM).
For code example, refer to A.3.5: Write to data EEPROM code example.
To Next Page
Loading...
Need help?
General
