Writing to Flash Memory

I don't quite understand how to write to the flash memory, even though I have read the User's Manual and other relevant documents.

A program cannot be directly rewritten by the user system.
Writing to the internal flash memory is performed using a dedicated programmer and parameter file.
Therefore, you yourself do not need to prepare a writing program.
Writing is performed by connecting to the programmer via the interface circuit described in the device manual.
For the actual writing method, refer to the manual of the programmer (such as PG-FP4).

When using the dedicated flash programmer in the UART mode, do I have to use a predetermined value for the V853 operation frequency?

To write to the flash memory, you basically need to set a clock of 10MHz or greater.
Alternatively, we advise you to use a frequency that enables a decrease in the UART baud rate error (an integer multiple of the transmission frequency: for example, 19.6608MHz).

What tools are required to write a program to the V853 (uPD703003) internal flash memory?

A flash programmer (PG-FP4 manufactured by NEC Electronics Corporation or FL-PR4 manufactured by Naito Densei Machida Mfg. Co., Ltd.) and a program adapter (FA-100GC manufactured by Naito Densei Machida Mfg. Co., Ltd) are required.
In the case of on-board writing (writing in a state in which the V853 flash product is mounted), only the dedicated programmer is needed; the socket adapter is not needed.

Contact Naito Densei Machida Mfg. Co., Ltd by phoning 045-475-4191 (Japan).
Their home page is http://www.ndk-m.co.jp/eng/index.html.

I hear that the uPD70F3025A writing method will be changed.
For devices for which the writing method has been changed, can I use the conventional writing method?

Yes, you can.
Even for a new device, writing is possible without changing the hardware.
In this case, however, the writing time cannot be reduced because only the conventional writing method can be used.
In addition, new devices have a different silicon signature and cannot be written with the same parameter file as that of the conventional device.
Make sure to use the parameter file that corresponds to the new device.