Flash Memory
274
Mitsubishi microcomputers
M16C / 62P Group
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
development
Preliminary Specifications Rev.1.0
Specifications in this manual are tentative and subject to change.
Software Commands
Software commands are described below. The command code and data must be read and written in 16-
bit units, to and from even addresses in the user ROM area. When writing command code, the 8 high-
order bits (D
1t
–D
8
) are ignored.
Table 1.27.4. Software Commands
Read Array Command (FF
16
)
This command reads the flash memory.
Writing ‘xxFF
16
’ in the first bus cycle places the microcomputer in read array mode. Enter the read
address in the next or subsequent bus cycles, and the content of the specified address can be read in
16-bit units.
Because the microcomputer remains in read array mode until another command is written, the con-
tents of multiple addresses can be read in succession.
Read Status Register Command (70
16
)
This command reads the status register.
Write ‘xx70
16
’ in the first bus cycle, and the status register can be read in the second bus cycle. (Refer
to “Status Register.”) When reading the status register too, specify an even address in the user ROM
area.
Do not execute this command in EW1 mode.
Command
Program
Clear status register
Read array
Read status register
(Note)
First bus cycle
Second bus cycle
Lock bit program
Erase all unlocked block
Block erase
Read lock bit status
Write
Write
Write
Write
Write
Write
Write
Write
Mode
Read
Write
Write
Write
Write
Write
Mode
X
BA
X
WA
BA
BA
Address
SRD
xxD0
16
xxD0
16
WD
xxD0
16
xxD0
16
Data
(D
0
to D
7
)
xxFF
16
xx70
16
xx50
16
xx40
16
xx77
16
xxA7
16
xx20
16
xx71
16
Data
(D
0
to D
7
)
X
X
X
WA
BA
X
X
X
Address
Note: It is only blocks 0 to 12 that can be erased by the Erase All Unlocked Block command.
Block A cannot be erased. Use the Block Erase command to erase block A.
SRD: Status register data (D
7
to D
0
)
WA: Write address (Make sure the address value specified in the the first bus cycle is the same even address
as the write address specified in the second bus cycle.)
WD: Write data (16 bits)
BA: Uppermost block address (even address, however)
X: Any even address in the user ROM area
x: High-order 8 bits of command code (ignored)