z8f1601 ZiLOG Semiconductor, z8f1601 Datasheet - Page 166

• Manufacturer Part Number: z8f1601
• Description: Z8 Encore!? Microcontroller With Flash Memory And 10-bit A/d Converter
• Manufacturer: ZiLOG Semiconductor

Option Bits
Overview
Operation
Option Bit Address Space
PS017609-0803
Option Bit Configuration By Reset
Option Bits allow user configuration of certain aspects of Z8F640x family device opera-
tion. The feature configuration data is stored in the Program Memory and read during
Reset. The features available for control via the Option Bits are:
•
•
•
•
Each time the Option Bits are programmed or erased, the Z8F640x family device must be
Reset for the change to take place. During any reset operation (System Reset, Short Reset,
or Stop Mode Recovery), the Option Bits are automatically read from the Program Mem-
ory and written to Option Configuration registers. The Option Configuration registers con-
trol operation of the Z8F640x family device. Option Bit control of the Z8F640x family
device is established before the device exits Reset and the eZ8 CPU begins code execu-
tion. The Option Configuration registers are not part of the Register File and are not acces-
sible for read or write access.
The first two bytes of Program Memory at addresses
the user Option Bits. The byte at Program Memory address
user options. The byte at Program Memory address
must be left in its unprogrammed state.
Watch-Dog Timer time-out response selection–interrupt or Short Reset.
Watch-Dog Timer enabled at Reset.
The ability to prevent unwanted read access to user code in Program Memory.
The ability to prevent accidental programming and erasure of all or a portion of the
user code in Program Memory.
0001H
0000H
is reserved for future use and
0000H
and
0001H
is used to configure
are reserved for
Z8 Encore!
Option Bits
®
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