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User’s Manual U15109EJ3V0UD
493
CHAPTER 17 FLASH MEMORY (
µµµµ
PD70F3089Y)
The
µ
PD70F3089Y is the flash memory version of the V850/SC1, V850/SC2, and V850/SC3 and incorporates a
512 KB flash memory.
Caution
There are differences in the amount of noise tolerance and noise radiation between flash
memory versions and mask ROM versions. When considering changing from a flash memory
version to a mask ROM version during the process from experimental manufacturing to mass
production, make sure to sufficiently evaluate commercial samples (CS) (not engineering
samples (ES)) of the mask ROM versions.
In the instruction fetch to this flash memory, 4 bytes can be accessed by a single clock as well as the mask ROM
version.
Writing to flash memory can be performed with memory mounted on the target system (on board). A dedicated
flash programmer is connected to the target system to perform writing.
The following can be considered as the development environment and the applications using flash memory.
•
Software can be altered after the V850/SC1, V850/SC2, and V850/SC3 are solder-mounted on the target
system.
•
Small scale production of various models is made easier by differentiating software.
•
Data adjustment in starting mass production is made easier.
17.1 Features
•
4-byte/1-clock access (in instruction fetch access)
•
All area batch erase/area unit erase
•
Communication via serial interface with the dedicated flash programmer
•
Erase/write voltage: V
PP
= 7.8 V
•
On-board programming
•
Flash memory programming by self rewriting in area (128 KB) units is possible
17.1.1 Erasing unit
This product has the following two erasure units.
(a) All area batch erase
The area of xx000000H to xx07FFFFH can be erased at the same time. The erasure time is 8.0 s.
(b) Area erase
Erasure can be performed in area units (there are four 128 KB unit areas). The erasure time is 2.0 s for each
area.
Area 0:
The area of xx000000H to xx01FFFFH (128 KB) is erased
Area 1:
The area of xx020000H to xx03FFFFH (128 KB) is erased
Area 2:
The area of xx040000H to xx05FFFFH (128 KB) is erased
Area 3:
The area of xx060000H to xx07FFFFH (128 KB) is erased