Z8FMC16100 Series Flash MCU
Product Specification
223
Option Bits
Option bits allow user configuration of certain aspects of the Z8FMC16100 Series Flash
MCU operation. The feature configuration data is stored in program memory and read
during Reset. The features available for control using the option bits are:
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Watch-Dog Timer time-out selection of interrupt or Reset
Watch-Dog Timer enabled at Reset
Code protection by preventing external read access of program memory
The ability to prevent accidental programming and erasure of program memory
Voltage Brown-Out can be disabled during STOP mode to reduce power consumption
External oscillator mode selection
Selectable PWM OFF state, output polarity, fault state, and Reset state
Disable PWM output pairs, enabling them as inputs
RESET/Fault0 pin function selection
Low power clock divide mode selection
Option Bit Types
Two types of option bits, user option bits and trim option bits, allow configuration of cer-
tain aspects of Z8FMC16100 Series Flash MCU operation. Each is described in this sec-
tion.
User Option Bits
The user option bits are contained in the first two bytes of program memory. Because
these locations contain application-specific device configuration, it is possible for the user
to alter these bytes by programming Flash memory.
Note: The information contained in these bytes is lost when page 0 of program memory is
erased.
Trim Option Bits
The trim option bits are contained in the information page of Flash memory. These bits are
factory-programmed values required to optimize the operation of on-board analog cir-
cuitry, and cannot be altered by the user. Program memory can be erased without endan-
gering these values.
PS024604-1005
P R E L I M I N A R Y
Option Bit Types
ZILOG [ ZILOG, INC. ]
