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CHAPTER 19 512K-BIT (64 KB) FLASH MEMORY
19.1 Overview of the 512K-Bit Flash Memory
The 512K-bit (64K bytes) flash memory is allocated in the FF bank on the CPU memory
map, and the function of the flash memory interface circuit enables the read/access or
program access from the CPU to the flash memory, same as the mask ROM. The write/
erase operation to the flash memory can be executed through the flash memory
interface circuit by executing an instruction issued from the CPU. Therefore, the flash
memory mounted can be rewritten under the control of the internal CPU, so that the
program or data can be upgraded or updated more efficiently.
However, no selector operation such as the enable sector protect can be used.
s Characteristics of the 512K-Bit Flash Memory
64K words x 8 bits/32K words x 16 bits (16K+8K+8K+32K) sector configuration
Use of automatic program algorithm (Embedded Algorithm: Equivalent to MBM29F400TA)
Erase pause/restart function provided
Detection of completion of writing/erasing using data polling or toggle bit functions
Detection of completion of writing/erasing using CPU interrupts
Compatibility with the JEDEC standard-type command
Sector erase function (any combination of sectors)
Number of write/erase operations 10,000 times guaranteed.
"Embedded Algorithm" is the trademark of Advanced Micro Device.
s Writing to/Erasing Flash Memory
The write/erase operation of the flash memory cannot be executed simultaneously. In executing
the data write/erase operation in the flash memory, only the write operation can be executed
without a program access from the flash memory, by copying a program on the flash memory to
RAM and executing the program.
For details, see Section 19.6.2, "Writing the Data".