32182 datasheet(144/755 Pages) RENESAS

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6-9

INTERNAL MEMORY

32182 Group User’s Manual (Rev.1.0)

FPROT = 0

FENTRY = 1

YES

FENTRY = 1

FPROT = 1

FPROT is not set to 1 if a write cycle

to any other area occurs during this time.

Figure 6.4.1 Protection Unlocking Flow

6.4 Registers Associated with the Internal Flash Memory

Flash Control Register 2 (FCNT2)

<Address: H’0080 01E3>

1011121314

b15

FPROT

Bit Name

Function

8–14

No function assigned. Fix to "0".

FPROT

0: Protection by lock bit effective

Unlock bit

1: Protection by lock bit invalidated

Flash Control Register 2 (FCNT2) controls invalidation of the internal flash memory protection by a lock bit

(protection against programming/erase operation). Protection of the internal flash memory is invalidated by

setting the FPROT bit to "1", so that any blocks protected by a lock bit can now be programmed or erased.

To set the FPROT bit to "1", write "0" and then "1" to the FPROT bit in succession while the FENTRY bit = "1". To

clear the FPROT bit to "0", write "0" to the FPROT bit.

If one of the following operations is attempted, the FPROT bit is cleared to "0".

1) Writing "0" to the FPROT bit

2) Entering a low-level signal to the FP pin

3) Clearing the FENTRY bit to "0"

4) Entering a low-level signal to the RESET# pin

32182 Datasheet(PDF) 144 Page - Renesas Technology Corp