UPD78F9500MA-CAC-A Datasheet, PDF (235/342 Pages) Renesas Technology Corp – 8-Bit Single-Chip Microcontrollers

CHAPTER 16 FLASH MEMORY
ACK
NAK
Table 16-6. Response Name
Command Name
Function
Acknowledges command/data.
Acknowledges illegal command/data.
16.7.3 Security settings
The operations shown below can be prohibited using the security setting command.
• Batch erase (chip erase) is prohibited
Execution of the block erase and batch erase (chip erase) commands for entire blocks in the flash memory is
prohibited. Once execution of the batch erase (chip erase) command is prohibited, all the prohibition settings can
no longer be cancelled.
Caution After the security setting of the batch erase is set, erasure cannot be performed for the device.
In addition, even if a write command is executed, data different from that which has already
been written to the flash memory cannot be written because the erase command is disabled.
• Block erase is prohibited
Execution of the block erase command in the flash memory is prohibited. This prohibition setting can be
cancelled using the batch erase (chip erase) command.
• Write is prohibited
Execution of the write and block erase commands for entire blocks in the flash memory is prohibited. This
prohibition setting can be cancelled using the batch erase (chip erase) command.
Remark The security setting is valid when the programming mode is set next time.
The batch erase (chip erase), block erase, and write commands are enabled by the default setting when the flash
memory is shipped. The above security settings are possible only for on-board/off-board programming. Each security
setting can be used in combination.
Table 16-7 shows the relationship between the erase and write commands when the 78K0S/KU1+ security function
is enabled.
Table 16-7. Relationship Between Commands When Security Function Is Enabled
Security
Command Batch Erase (Chip
Erase) Command
Block Erase
Command
Write Command
When batch erase (chip erase) security
operation is enabled
Disabled
Disabled
Enabled^Note
When block erase security operation is
enabled
Enabled
Enabled
When write security operation is enabled
Disabled
Note Since the erase command is disabled, data different from that which has already been written to the
flash memory cannot be written.
User’s Manual U18172EJ3V0UD
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