CHAPTER 18 FLASH MEMORY
Preliminary User’s Manual U16898EJ1V0UD
263
Table 18-2. Basic Functions
Support (
{
: Supported,
×
: Not supported)
Function Functional
Outline
On-Board/Off-Board
Programming
Self Programming
Block erasure
The contents of specified memory blocks
are erased.
{
{
Chip erasure
The contents of the entire memory area
are erased all at once.
{
×
Write
Writing to specified addresses, and a
verify check to see if write level is secured
are performed.
{
{
Checksum
Data read from the flash memory is
compared with data transferred from the
flash programmer.
{
×
Security setting
Use of the block erase command, chip
erase command, and program command
can be prohibited.
{
×
(Only values set by on-
board/off-board programming
can be retained)
The following table lists the security functions. The block erase command prohibit, chip erase command prohibit,
and program command prohibit functions are enabled by default after shipment, and security can be set by rewriting
via on-board/off-board programming. Each security function can be used in combination with the others at the same
time.
Table 18-3. Security Functions
Rewriting Operation When Prohibited
(
{
: Executable,
×
: Not Executable)
Function Function
Outline
On-Board/Off-Board
Programming
Self Programming
Block erase
command
prohibit
Execution of a block erase command on
all blocks is prohibited. Setting of
prohibition can be initialized by execution
of a chip erase command.
Block erase command:
×
Chip erase command:
{
Program command:
{
Chip erase
command
prohibit
Execution of block erase and chip erase
commands on all the blocks is prohibited.
Once prohibition is set, setting of
prohibition cannot be initialized because
the chip erase command cannot be
executed.
Block erase command:
×
Chip erase command:
×
Program command:
{
Program
command
prohibit
Write and block erase commands on all
the blocks are prohibited. Setting of
prohibition can be initialized by execution
of the chip erase command.
Block erase command:
×
Chip erase command:
{
Program command:
×
Can always be rewritten
regardless of setting of
prohibition
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