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20.4 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
Table 20.4-1 "Command Sequence Table" lists the commands used for flash memory write/
erase. All of the data written to the command register is in bytes, but use word access to write.
The data in the high-order bytes at this time is ignored.
Note:
The addresses Fx in the table mean FF and FE. Use these addresses as the access target
bank values for operations.
The addresses in the table are the values in the CPU memory map. All addresses and data
are represented using hexadecimal notation. However, the letter X is an optional value.
RA: Read address
PA: Write address. Only even addresses can be specified.
SA: Sector address. See Section
20.2 "1M-Bit Flash Memory Sector
Configuration".
RD: Read data
PD: Write data. Only word data can be specified.
*1 Both of the two types of Read/Reset commands can reset the flash memory to read mode.
Table 20.4-1 Command Sequence Table
Command
sequence
Bus
write
access
1st bus write
cycle
2nd 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)
1
FxXXXX
XXF0
-
Read/Reset
(*1)
4
FxAAAA
XXAA
Fx5554
XX55
FxAAAA
XXF0
RA
RD
-
Write
program
4
FxAAAA
XXAA
Fx5554
XX55
FxAAAA
XXA0
PA
(even)
PD
(word)
---
-
Chip Erase
6
FxAAAA
XXAA
Fx5554
XX55
FxAAAA
XX80
FxAAAA
XXAA
Fx5554
XX55
FxAAAA
XX10
Sector Erase
6
FxAAAA
XXAA
Fx5554
XX55
FxAAAA
XX80
FxAAAA
XXAA
Fx5554
XX55
SA
(even)
XX30
Sector Erase Suspend
Entering address FxXXXX data (xxB0H) suspends erasing during sector erase.
Sector Erase Restart
Entering address FxXXXX data (xx30H) restarts erasing after erasing is suspended during sector erase.