UPD78F9222MC(T)-5A4-A NEC, UPD78F9222MC(T)-5A4-A Datasheet - Page 276

• Manufacturer Part Number: UPD78F9222MC(T)-5A4-A
• Description: 8BIT MCU, 4K FLASH, 256B RAM, 78F9222
• Manufacturer: NEC

Specifications of UPD78F9222MC(T)-5A4-A

• Controller Family/series: UPD78
• No. Of I/o's: 17
• Ram Memory Size: 256Byte
• Cpu Speed: 10MHz
• No. Of Timers: 4
• No. Of: RoHS Compliant
• Core Size: 8bit
• Program Memory Size: 4KB
• Oscillator Type: External, Internal

18.8 Flash Memory Programming by Self Programming
program, making it possible to upgrade programs in the field.
18.8.1 Outline of self programming
self programming mode. Write/erase processing for the flash memory, which has been set to the register in advance,
is performed by executing the HALT instruction during self programming mode. The HALT state is automatically
released when processing is completed.
Example of shifting normal mode to self programming mode for details.
diagram, Table 18-10 lists the commands for controlling self programming.
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Table 18-8 shows the relationship between the security setting and the operation in each programming mode.
The 78K0S/KA1+ supports a self programming function that can be used to rewrite the flash memory via a user
Caution Self programming processing must be included in the program before performing self
Remarks 1. For usage of self programming, refer to the examples from 18.8.4. onward.
To execute self programming, shift the mode from the normal operation of the user program (normal mode) to the
To shift to the self programming mode, execute a specific sequence for a specific register. Refer to 18.8.4
Remark
Figure 18-8 shows a block diagram for self programming, Figure 18-9 shows the self programming state transition
Notes 1. Execution of each command is prohibited by the security setting.
Security Setting
Batch erase (chip erase)
Block erase
Write
Table 18-8. Relationship Between Security Setting and Operation In Each Programming Mode
Note Maskable interrupt servicing is disabled during self programming mode.
Normal mode
Self programming mode
2. Execution of self programming command is possible regardless of the security setting.
programming.
Data written by self programming can be referenced with the MOV instruction.
2. To use the internal flash memory of the 78K0S/KA1+ as the external EEPROM for storing data, refer
to 78K0S/Kx1+ EEPROM Emulation Application Note (U17379E).
Programming Mode
Mode
Possible
Security Setting
Table 18-9. Self Programming Mode
On-Board/Off-Board Programming
CHAPTER 18 FLASH MEMORY
User’s Manual U16898EJ5V0UD
User Program Execution
Enabled
Enabled
Valid
Security Operation
Note
Note 1
Execution of Write/erase for Flash
Impossible
Memory with HALT Instruction
Security Setting
Self Programming
Enabled
−
Invalid
Security Operation
Note 2