![](http://datasheet.mmic.net.cn/30000/M32176F3TFP_datasheet_2359466/M32176F3TFP_134.png)
6
6-10
INTERNAL MEMORY
32176 Group User’s Manual (Rev.1.01)
6.4 Registers Associated with the Internal Flash Memory
Flash Control Register 2 (FCNT2)
<Address: H’0080 07E3>
<Upon exiting reset: H’00>
b
Bit Name
Function
R
W
8–10
No function assigned. Fix to "0".
00
11
FLOCKS
0: Memory area read mode
R(Note 1)
Lock bit read mode select bit
1: Register read mode
12–14
No function assigned. Fix to "0".
00
15
FPROT
0: Protection by lock bit effective
R(Note 1)
Lock bit protect control bit
1: Protection by lock bit invalidated
Note 1: It can be accessed for write only during the Flash E/W entry mode (FENTRY bit = "1").
(1) FLOCKS (Lock Bit Read Mode Select) bit (Bit 11)
The FLOCKS bit is used to select a method for reading out the lock bit status. When the FLOCKS bit = "0", the
internal flash memory is placed in memory area read mode, so that it is possible to inspect the lock bit status
by issuing command data H’7171 to any address of the flash memory and then reading the last even address
of the target block. When the FLOCKS bit = "1", the internal flash memory is placed in register read mode, so
that it is possible to inspect the lock bit status by first issuing command data H’7171 and H’D0D0 to any
address of the target block in succession and then, when the FBUSY bit is set to "1", by reading the FLOCKST
bit in Flash Control Register 4.
The FLOCKS bit can only be accessed for write when the FENTRY bit = "1".
If one of the following operations is attempted, the FLOCKS bit is cleared to "0".
1) Writing "0" to the FLOCKS 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
(2) FPROT (Lock Bit Protect Control) bit (Bit 15)
The FPROT bit 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
b8
9
10
11121314
b15
FLOCKS
FPROT
000
0000
0