M16C Datasheet, PDF (238/262 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
Erase All Unlocked Blocks Command (A716/D016)
Writing the "A716" command code for the first bus cycle and the "D016" verify command code for the
second bus cycle continuously executes the block erase operation for all the blocks. In this case, it is not
necessary to specify an address in the second bus cycle.
Even after the erase all unlock blocks operation ends, as with block erase, the end of the operation can be
verified by reading the status register or the status of the RY/BY signal. Also, the result of the erase
operation can be known by reading the status register.
When the WP pin is "H" level, all blocks are erased regardless of lock bit status. When the WP pin is "L"
level, The lock pin is enabled and only unlocked blocks (lock bit data are "1") are erased.
Lock Bit Program Command (7716/D016)
Writing the "7716" command code for the first bus cycle and, after that, the "D016" verify command code as
well as the block address of a block for the second bus cycle writes "0" (lock) for the lock bit of the
specified block.
Figure 24-5 shows an example of flowchart of the lock bit program. The lock bit status (lock bit data) can
be read with the read lock bit status command.
As with the page program, the end of the lock bit program auto write operation can be verified by reading
the status register or the status of the RY/BY signal.
For information on the lock bit function, reset procedure and so on, see the section on the data protection
function.
Start
Write 7716
Write D016 and block
address
SR7=1? ^NO
YES
SR4=0? ^NO
YES
Lock bit program end
Lock bit program error
Figure 24-5. Lock bit program flowchart
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