ZLF645 MAXIM [Maxim Integrated Products], ZLF645 Datasheet - Page 183

• Manufacturer Part Number: ZLF645
• Description: Flash MCUs with Learning Amplification
• Manufacturer: MAXIM [Maxim Integrated Products]

Table 86. User Option Byte 1 Shadow Register (OPT1SR)
19-4572; Rev 0; 4/09
[0]
Bit
Field
Reset State
CPU Access (R/W)
Register Address (R/W)
Note:
RESERVED bits when read by the CPU will return 0 and when written have no effect.
1
0
FLRWP —Flash Main Memory Protect
Flash Main Memory and Information Area Page 3 can be read, programmed,
and erased by both the Flash Byte Programming interface or through the ICP
interface.
Reads and writes to the Flash main memory and writes and erasures to
Information Area Page 3 by the ICP or Flash Byte Programming interfaces is
disabled unless, with this bit 0, a main memory mass erase is completed first.
A main memory mass erase causes resetting of this bit value in the Option
Byte 1 shadow register to a 1 but does not effect the corresponding Flash
memory bit. Once the Option Byte 1 shadow register bit is reset, the ICP or
Flash Byte Programming interface is allowed full read, write, and erase access
to the Flash’s main memory and to Page 3 of the Information Area and can
reset the corresponding Flash memory bit.
X
7
RESERVED
X
6
X
5
Bank D: 0Fh; Linear: D0Fh
X
4
16BITSTK DIVBY1 FLPROT1 FLRWP
R/W
X
3
ZLF645 Series Flash MCUs
R/W
2
1
Product Specification
R
X
1
Operation
X
R
0
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