M16C Datasheet, PDF (242/262 Pages) Mitsubishi Electric Semiconductor – SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER

Preliminary Specifications REV.B
Specifications in this manual are tentative and subject to change.
Mitsubishi microcomputers
M16C / 6N Group
Parallel I/O Mode
SINGLE-CHIP 16-BIT CMOS MICROCOMPUTER
Block Status After Program (SR3)
If excessive data are written (phenomenon whereby the memory cell becomes depressed which
results in data not being read correctly), the block status after-program is set to "1" at the end of the
page write operation. In other words, when writing ends successfully, "8016" is output; when writing
fails, "9016" is output; and when excessive data are written, "8816" is output.
If "1" is written for any of SR5-, SR4- or SR3 bits, the page program-, block erase-, erase all unlocked
blocks- and lock bit program commands are not accepted. Before executing these commands,,
execute the clear status register command (5016) and clear the status register.
Also in the following cases, both SR4 and SR5 are set to "1" (command sequence error).
(1) If data other than "D016" or "FF16" are input for the second bus cycle data of the lock bit
program command (7716/D016).
(2) If data other than "D016" or "FF16" are input for the second bus cycle data of the block erase
command (2016/D016).
(3) If data other than "D016" or "FF16" are input for the second bus cycle data of the erase all
unlocked blocks command (A716/D016). However, inputting "FF16" engages the read array
mode and cancels the setup command in the first bus cycle.
Full Status Check
Results of executed erase- and program operations can be known by running a full status check.
Figure 24-7 shows a flowchart of the full status check and explains how to remedy errors which may
occur.
Read status register
YES
SR4=1 and SR5
=1 ?
Command
sequence error
NO
SR5=0? ^{NO Block erase error}
YES
SR4=0?
NO _{Program error (page}
or lock bit)
YES
SR3=0? ^NO
YES
End (block erase, program)
Program error
(block)
Execute the clear status register command (5016)
to clear the status register. Try performing the
operation one more time after confirming that the
command is entered correctly.
Should a block erase error occur, the block in error
cannot be used.
Execute the read lock bit status command (7116)
to see if the block is locked. After removing lock,
execute write operation in the same way. If the
error still occurs, the page in error cannot be
used.
After erasing the block in error, execute write
operation one more time. If the same error still
occurs, the block in error cannot be used.
Note: When one of SR5 to SR3 is set to 1, none of the page program, block erase,
erase all unlock blocks and lock bit program commands is accepted. Execute the
clear status register command (5016) before executing these commands.
Figure 24-7. Full status flowchart and remedial procedure for errors
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