z8f0813 ZiLOG Semiconductor, z8f0813 Datasheet - Page 149

• Manufacturer Part Number: z8f0813
• Description: High-performance 8-bit Microcontrollers
• Manufacturer: ZiLOG Semiconductor

Table 82. Flash Sector Protect Register (FPROT)
BITS
FIELD
RESET
R/W
ADDR
PS024314-0308
Caution:
Flash Sector Protect Register
Flash Frequency High and Low Byte Registers
SPROT7
R/W
7
0
The Flash Sector Protect (FPROT) register is shared with the Flash Page Select Register.
When the
this address targets the Flash Sector Protect Register. In all other cases, it targets the Flash
Page Select Register.
This register selects one of the 8 available Flash memory sectors to be protected. The reset
state of each Sector Protect bit is an unprotected state. After a sector is protected by setting
its corresponding register bit, it cannot be unprotected (the register bit cannot be cleared)
without powering down the device.
SPROT7-SPROT0—Sector Protection
Each bit corresponds to a 512 bytes Flash sector. For the Z8F08x3 devices, the upper 3 bits
must be zero. For the Z8F04x3 devices all bits are used. For the Z8F02x3 devices, the
upper 4 bits are unused. For the Z8F01x3 devices, the upper 6 bits are unused.
The Flash Frequency High (FFREQH) and Low Byte (FFREQL) 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) and is calculated using the following equation:
The Flash Frequency High and Low Byte registers must be loaded with the correct value
to ensure proper operation of the device. Also, Flash programming and erasure is not
supported for system clock frequencies below 20 kHz or above 20 MHz.
FFREQ[15:0]
SPROT6
R/W
Flash Control Register
6
0
=
SPROT5
{
R/W
FFREQH[7:0],FFREQL[7:0]
5
0
SPROT4
is written with
R/W
4
0
FF9H
SPROT3
R/W
3
0
73H
}
=
followed by
System Clock Frequency
----------------------------------------------------------------- -
Z8 Encore! XP
SPROT2
R/W
2
0
Product Specification
1000
5EH
SPROT1
, the next write to
R/W
1
0
®
F0823 Series
Flash Memory
SPROT0
R/W
0
0
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