UPD78F9502MA-CAC-A NEC, UPD78F9502MA-CAC-A Datasheet - Page 144

• Manufacturer Part Number: UPD78F9502MA-CAC-A
• Description: 8BIT MCU, 4K FLASH, 128B RAM, SMD
• Manufacturer: NEC

Specifications of UPD78F9502MA-CAC-A

• Controller Family/series: UPD78F
• No. Of I/o's: 8
• Ram Memory Size: 128Byte
• Cpu Speed: 10MHz
• No. Of Timers: 2
• No. Of Pwm: RoHS Compliant
• Core Size: 8bit
• Program Memory Size: 4KB
• Oscillator Type: External, Internal

14.8 Flash Memory Programming by Self Writing
memory via a user program, making it possible to upgrade programs in the field.
14.8.1 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 for details.
diagram, Table 14-8 lists the commands for controlling self programming.
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Table 14-6 shows the relationship between the security setting and the operation in each programming mode.
The PD78F9500, 78F9501, 78F9502 support a self programming function that can be used to rewrite the flash
Caution
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 14.8.4
Remark
Figure 14-6 shows a block diagram for self programming, Figure 14-7 shows the self programming state transition
Remarks 1.
Notes 1. Execution of each command is prohibited by the security setting.
Security Setting
Batch erase (chip erase)
Block erase
Write
Table 14-6. 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.
Data written by self programming can be referenced with the MOV instruction.
Self programming processing must be included in the program before performing self writing.
2. To use the internal flash memory of the PD78F9500, 78F9501, 78F9502 as the external EEPROM
for storing data, refer to “78K0S/Kx1+ EEPROM Emulation Application Note” (U17379E).
Programming Mode
For usages of self programming, refer to use example mentioned in after 14.8.4.
Mode
Possible
Security Setting
Table 14-7. Self Programming Mode
On-Board/Off-Board Programming
Preliminary User’s Manual U18681EJ1V0UD
CHAPTER 14 FLASH MEMORY
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