M3885 Datasheet, PDF (78/103 Pages) Renesas Technology Corp – SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER

MITSUBISHI MICROCOMPUTERS
3885 Group
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
Program Command (4016)
The program operation starts when the command code “4016” is writ-
ten in the first bus cycle. Then, if the address and data to program
are written in the 2nd bus cycle, program operation (data program-
ming and verification) will start.
Whether the write operation is completed can be confirmed by read-
_____
ing the status register or the RY/BY signal status. When the program
starts, the read status register mode is accessed automatically and
the content of the status register can be read out from the data bus
(D0–D7). The status register bit 7 (SR7) is set to “0” at the same time
the write operation starts and is returned to “1” upon completion of
the write operation. In this case, the read status register mode re-
mains active until the read array command (FF16) is written.
____
The RY/BY pin is “L” during write operation and “H” when the write
operation is completed as is the status register bit 7.
At program end, program results can be checked by reading the sta-
tus register.
Block Erase Command (2016/D016)
By writing the command code “2016” in the first bus cycle and the
confirmation command code “D016” in the second bus cycle that
follows to the block address of a flash memory block, the system
initiates a block erase (erase and erase verify) operation.
Whether the block erase operation is completed can be confirmed
____
by reading the status register or the RY/BY signal. At the same time
the block erase operation starts, the read status register mode is
automatically entered, so the content of the status register can be
read out. The status register bit 7 (SR7) is set to “0” at the same time
the block erase operation starts and is returned to “1” upon comple-
tion of the block erase operation. In this case, the read status regis-
ter mode remains active until the read array command (FF16) is writ-
ten.
____
The RY/BY pin is “L” during block erase operation and “H” when the
block erase operation is completed as is the status register bit 7.
After the block erase operation is completed, the status register can
be read out to know the result of the block erase operation. For de-
tails, refer to the section where the status register is detailed.
Start
Write 4016
Write ^{Write address}
Write data
Status register
read
SR7=1?
NO
or
RY/BY=1?
YES
SR4=0?
YES
Program
completed
NO _Program
error
In this case, the read status
register mode remains
active until the read array
command (FF16) is written.
Fig. 74 Page program flowchart
Start
Write 2016
Write
D016
Block address
Status register
read
SR7=1?
NO
or
RY/BY=1?
YES
NO
SR5=0?
Erase error
YES
Erase completed
In this case, the read status
register mode remains active
until the read array command
(FF16) is written.
Fig. 75 Block erase flowchart
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