Table of Contents
Advertisement
CHAPTER 19 512 KBIT FLASH MEMORY
19.4
Flash Memory Write Control Register (FWR0/1)
The flash memory write control register (FWR0/1) is a register in the flash memory
interface, used to set the accidental write preventive function for the flash memory.
I Flash memory write control register (FWR0/1)
The flash memory write control register (FWR0/1) contains the write-enable/protect bits for
individual sectors (SA0 to SA9). The initial value of the bits is "0" to disable writing to the sectors.
Writing "1" to one of the bits enabled to write the corresponding sector. Writing "0" to it prevents
an accidental write from being executed to the sector. Once you have written "0" to the bit,
therefore, you cannot write to the sector even though you write "1" to the bit. When you write to
the sector again, you have to reset the bit.
R/W : Read/write enabled
0
: Write protected [Initial value]
1
: Write enabled
582
Figure 19.4-1 Flash Memory Write Control Register (FWR0/1)
bit 7
FWR0
[390AH]
SA7E SA6E SA5E SA4E SA3E SA2E SA1E SA0E
(
0
)
R/W
bit 15
FWR1
-
[390BH]
(
0
R/W
6
5
4
(
0
)
(
0
)
(
0
)
R/W
R/W
R/W
14
13
12
-
-
-
)
(
)
(
)
(
)
0
0
0
R/W
R/W
R/W
3
2
1
0
(
0
)
(
0
)
(
0
)
(
0
R/W
R/W
R/W
R/W
11
10
9
8
-
-
SA9E SA8E
(
)
(
)
(
)
(
0
0
0
0
R/W
R/W
R/W
R/W
)
)
Advertisement
Table of Contents
