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CHAPTER 16 FLASH MEMORY
When this bit is "1", writing data and commands to the flash memory becomes valid and the
automatic algorithm can be started. However, data from flash memory is read in 16-bit
access mode, during which flash memory cannot be used as program memory because 32-
bit access is inhibited.
When overwriting this bit, ensure that the RDY bit has caused a stop of the automatic
algorithm (write/erase). When the RDY bit is "0", the value of this bit cannot be changed.
This bit is initialized to "0" during a reset. Read and write operations are enabled.
0: inhibits writing to the flash memory and enables 32-bit read operations (ROM mode)
[this is the initial value].
1: enables writing to flash memory and inhibits 32-bit read operations (programming mode).
[bit 4] RDY (ReaDY)
The RDY bit indicates the operation status of the automatic algorithm (write/erase).
When this bit is "0", the automatic algorithm is executing a write or erase operation and
another Write or Erase command cannot be accepted. Data also cannot be read from an
address in flash memory. Reading this bit indicates the status of flash memory.
For details, see Section 16.7, "Execution Status of the Automatic Algorithm."
This bit is initialized to "0" during a reset. Read and write operations are enabled.
0: Writing or erasing is in progress, flash memory is not ready to accept a new Read,
Write, or Erase command
1: Flash memory is ready to accept a new Read, Write, or Erase command.
[bit 3 to 1] (reserved bit)
These bits are reserved bits. Their values during read operations are undefined, and they do
not affect write operations.
[bit 0] (reserved bit)
This bit is a reserved bit. Read operations for this bit return "0". Always set this bit to "0".
When the bit is set to "1", the results of subsequent operations may become uncertain.
This bit is initialized to "0" during a reset.
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