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CHAPTER 19 512K-BIT (64 KB) FLASH MEMORY
19.4 Starting the Flash Memory Automatic Algorithm
Four types of commands are available for starting the flash memory automatic
algorithm: Read/Reset, Write, and Chip Erase. Control of suspend and restart is
enabled for sector erase.
s Command Sequence Table
All the data is written to the command register in units of bytes, though it should be accessed
and written in units of words.
In this case, the data in the upper bytes is ignored.
Table 19.4-1 Command Sequence Table
Command
sequence
Bus
write
cycle
1st bus write
cycle
2 nd bus write
cycle
3rd bus write cycle
4th bus write cycle
5th bus write
cycle
6th bus write
cycle
Address
Data
Address
Data
Address
Data
Address
Data
Address
Data
Address
Data
Read/reset
1
FFXXXXH
XXF0H
---
-
---
-
Read/reset
4
FFAAAAH
XXAAH
FF5554H
XX55H
FFAAAAH
XXF0H
RA
RD
-
Write
program
4
FFAAAAH
XXAAH
FF5554H
XX55H
FFAAAAH
XXA0H
PA (even)
PD (word)
-
Chip erase
6
FFAAAAH
XXAAH
FF5554H
XX55H
FFAAAAH
XX80H
FFAAAAH
XXAAH
FF5554H
XX55H
FFAAAAH
XX10H
Sector erase
6
FFAAAAH
XXAAH
FF5554H
XX55H
FFAAAAH
XX80H
FFAAAAH
XXAAH
FF5554H
XX55H
SA (even)
XX30H
Sector erase suspend
Entering address "FFXXXXH" data (xxB0H) suspends erasing during sector erase.
Sector erase restart
Entering address "FFXXXXH" data (xx30H) .restarts erasing after erasing is suspended during sector erase.
* : Two types of read/reset commands can reset the flash memory to the read mode.
Note:
The addresses in the above table are the values on the CPU memory map. "X" is an optional value.
RA: Read address
PA: Write address. Only the even address can be specified.
SA: Sector address. For details, see Sectio
n 19.2 "512K-Bit Flash Memory Sector Configuration".
The even address can be specified.
RD: Read data
PD: Write data. Only the word data can be specified.