Z8F082A28100KIT ZILOG [Zilog, Inc.], Z8F082A28100KIT Datasheet - Page 148

• Manufacturer Part Number: Z8F082A28100KIT
• Description: Z8 Encore XP-R F08xA Series with eXtended Peripherals
• Manufacturer: ZILOG [Zilog, Inc.]

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PS024705-0405
Caution:
Flash Operation Timing Using the Flash Frequency Registers
Flash Code Protection Against External Access
Flash Code Protection Against Accidental Program and Erasure
FFREQ[15:0]
Before performing either a program or erase operation on Flash memory, the user must
first configure the Flash Frequency High and Low Byte registers. The Flash Frequency
registers allow programming and erasing of the Flash with system clock frequencies rang-
ing from 32KHz (32768Hz) through 20MHz.
The Flash Frequency High and Low Byte registers combine to form a 16-bit value,
FFREQ, to control timing for Flash program and erase operations. The 16-bit binary Flash
Frequency value must contain the system clock frequency (in KHz). This value is calcu-
lated using the following equation:
The user code contained within the Flash memory can be protected against external access
with the On-Chip Debugger. Programming the FRP Flash Option Bit prevents reading of
the user code with the On-Chip Debugger. Refer to the chapter
and the chapter
The Z8 Encore! XP
program and erasure of the Flash memory contents. This protection is provided by a com-
bination of the Flash Option bits, the register locking mechanism, the page select redun-
dancy and the sector level protection control of the Flash Controller.
Flash Code Protection Using the Flash Option Bits
The FHSWP and FWP Flash Option Bits combine to provide three levels of Flash Program
Memory protection as listed in Table 78. Refer to the chapter
for more information.
Flash programming and erasure are not supported for system clock frequencies below
32KHz (32768Hz) or above 20MHz. The Flash Frequency High and Low Byte registers
must be loaded with the correct value to ensure operation of the Z8 Encore! XP
Series devices.
“On-Chip Debugger” on page 148
=
®
System Clock Frequency (Hz)
--------------------------------------------------------------------------- -
F08xA Series provides several levels of protection against accidental
P R E L I M I N A R Y
1000
for more information.
Z8 Encore! XP
“Flash Option Bits” on page 138
“Flash Option Bits” on page 138
Product Specification
®
F08xA Series
Flash Memory
®
F08xA
130