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INTERNAL MEMORY
32180 Group User’s Manual (Rev.1.0)
6.9 Precautions To Be Taken when Rewriting the Internal Flash Memory
6.9 Precautions To Be Taken when Rewriting the Internal Flash Memory
The following describes precautions to be taken when programming/erasing the internal flash memory.
• When the internal flash memory is programmed or erased, a high voltage is generated internally. Because mode
transitions during programming/erase operation may cause the chip to break down, make sure the mode setting
pin/power supply voltages do not fluctuate to prevent unintended changes of modes.
• If the system uses any pins that are to be used by a general-purpose programming/erase tool, care must be
taken to prevent adverse effects on the system when the tool is connected.
• If the internal flash memory needs to be protected while using a general-purpose programming/erase tool, set
any ID in the flash memory protect ID verification area (H’0000 0084 to H’0000 008F).
• If the internal flash memory does not need to be protected while using a general-purpose programming/erase
tool, fill the entire flash memory protect ID verification area (H’0000 0084 to H’0000 008F) with H’FF.
• If the Flash Status Register 2 (FSTAT2)’s each error status is to be cleared (initialized to H’80) by resetting the
Flash Control Register 4 (FCNT4) FRESET bit, check to see that the Flash Status Register 1 (FSTAT1) FSTAT
bit = "1" (ready) before clearing the error status.
• Before resetting the Flash Control Register 1 (FCNT1) FENTRY bit from "1" to "0", check to see that the Flash
Status Register 1 (FSTAT1) FSTAT bit = "1" (ready) or the Flash Status Register 2 (FSTAT2) FBUSY bit = "1"
(ready).
• Do not clear the FENTRY bit if the Flash Status Register 1 (FSTAT1) FSTAT bit = "0" (busy) or the Flash Status
Register 2 (FSTAT2) FBUSY bit = "0" (being programmed or erased).
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