UPD78F4046GC-3B9 NEC, UPD78F4046GC-3B9 Datasheet - Page 19

• Manufacturer Part Number: UPD78F4046GC-3B9
• Description: 16-BIT SINGLE-CHIP MICROCONTROLLER
• Manufacturer: NEC

7.4 Cautions When Writing to Flash Memory
set the flash programmer as follows when writing to flash memory using these functions. Either 1-bit or 8-bit
memory manipulation instructions can be used to make these settings.
For writing data to the flash memory of the PD78F4046, use the prewrite and ECC functions. Moreover,
(1) Using prewrite function
(2) Using ECC function
<1> Creating ECC data
<2> Flash programmer (Flashpro II, Flashpro III) setting and writing
To improve flash memory rewrite characteristics, prewriting is necessary before erasing. Prewriting involves
writing 00H to all the data. This is performed to delete the bits that are already 1 in the data (erasure state),
and to prevent further erasure stress.
When writing to the PD78F4046 and shipping it as a product, ECC data needs to be written in the ECC data
area of flash memory. By writing ECC data and setting the ECC function, data writing can be performed
correctly.
Convert the EX file to an ECC-attached HEX file using the ECC generator included in the assembly package
(Ver. 1.20 or later for PC). Download this ECC-attached HEX file to the flash programmer, and then write.
[ECC data creating method]
• Prepare the HEX file created by the object converter of the assembly package.
• Convert it to the program data + HEX file using the ECC generator (ECCGEN.EXE) included in the assembly
Prewriting and ECC writing are performed by Flashpro II and Flashpro III. The setting method when using
an earlier version than Flashpro II Ver. 2.50 is described below.
Remark If using Flashpro II Ver. 2.50 or later or Flashpro III (PG-FP3 (Ver. 3.040 or later, products of NEC
package.
Example Convert the file “file.hex” to “file_ec.hex”.
Corporation)), setting is not necessary. Setting is performed automatically by reading parameter
files.
ec file.hex-ofile_ec.hex -a0ffffh, 10000h, 14000h, 14004h
Data Sheet U11447EJ2V0DS00
PD78F4046
19