Z8F0113HJ005EG Datasheet, PDF (162/245 Pages) Zilog, Inc. – High-Performance 8-Bit Microcontrollers

Z8 Encore! XP^® F0823 Series
Product Specification
147
Option Bit Types
This section describes the five types of Flash option bits offered in the F083A Series.
User Option Bits
The user option bits are contained in the first two bytes of program memory. Access to
these bits has been provided because these locations contain application-specific device
configurations. The information contained here is lost when page 0 in program memory is
erased.
Trim Option Bits
The trim option bits are contained in a Flash memory information page. These bits are fac-
tory programmed values required to optimize the operation of onboard analog circuitry
and cannot be permanently altered. Program memory may be erased without endangering
these values. It is possible to alter working values of these bits by accessing the Trim Bit
Address and Data Registers, but these working values are lost after a power loss or any
other reset event.
There are 32 bytes of trim data. To modify one of these values the user code must first
write a value between 00H and 1FH into the Trim Bit Address Register. The next write to
the Trim Bit Data Register changes the working value of the target trim data byte.
Reading the trim data requires the user code to write a value between 00H and 1FH into the
Trim Bit Address Register. The next read from the Trim Bit Data Register returns the
working value of the target trim data byte.
Note: The trim address range is from information address 20–3F only. The remainder of the
information page is not accessible through the trim bit address and data registers.
Calibration Option Bits
The calibration option bits are also contained in the information page. These bits are fac-
tory programmed values intended for use in software correcting the device’s analog per-
formance. To read these values, the user code must employ the LDC instruction to access
the information area of the address space as defined in the Flash Information Area section
on page 15.
Serialization Bits
As an optional feature, Zilog is able to provide factory-programmed serialization. For seri-
alized products, the individual devices are programmed with unique serial numbers. These
serial numbers are binary values, four bytes in length. The numbers increase in size with
each device, but gaps in the serial sequence may exist.
PS024315-1011
PRELIMINARY
Operation