Z8F041APH020SG2156 ZiLOG, Z8F041APH020SG2156 Datasheet - Page 167

• Manufacturer Part Number: Z8F041APH020SG2156
• Description: 8-bit Microcontrollers - MCU 4K FLASH 1K RAM 128B NVDS
• Manufacturer: ZiLOG

Specifications of Z8F041APH020SG2156

• Rohs: yes
• Core: eZ8
• Processor Series: Z8F041xx
• Data Bus Width: 8 bit
• Maximum Clock Frequency: 20 MHz
• Program Memory Size: 4 KB
• Data Ram Size: 1 KB
• On-chip Adc: Yes
• Operating Supply Voltage: 2.7 V to 3.6 V
• Operating Temperature Range: - 40 C to + 105 C
• Package / Case: PDIP-20
• Mounting Style: Through Hole
• A/d Bit Size: 10 bit
• A/d Channels Available: 8
• Interface Type: UART
• Maximum Operating Temperature: + 105 C
• Minimum Operating Temperature: - 40 C
• Number Of Programmable I/os: 17
• Number Of Timers: 2
• Program Memory Type: Flash
• Supply Voltage - Max: 3.6 V
• Supply Voltage - Min: 2.7 V

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PS022827-1212
Flash Code Protection Using the Flash Controller
At Reset, the Flash Controller locks to prevent accidental program or erasure of the Flash
memory. To program or erase the Flash memory, first write the Page Select Register with
the target page. Unlock the Flash Controller by making two consecutive writes to the
Flash Control Register with the values
ter must be rewritten with the target page. If the two Page Select writes do not match, the
controller reverts to a locked state. If the two writes match, the selected page becomes
active. See
After unlocking a specific page, you can enable either Page Program or Erase. Writing the
value
tected. Any other value written to the Flash Control Register locks the Flash Controller.
Mass Erase is not allowed in the user code but only in through the Debug Port.
After unlocking a specific page, you can also write to any byte on that page. After a byte is
written, the page remains unlocked, allowing for subsequent writes to other bytes on the
same page. Further writes to the Flash Control Register cause the active page to revert to a
locked state.
Sector-Based Flash Protection
The final protection mechanism is implemented on a per-sector basis. The Flash memories
of Z8 Encore! XP devices are divided into maximum number of 8 sectors. A sector is 1/8
of the total Flash memory size unless this value is smaller than the page size – in which
case, the sector and page sizes are equal. On Z8 Encore! F082A Series devices, the sector
size is varied according to the Flash memory configuration shown in
146.
The Flash Sector Protect Register can be configured to prevent sectors from being pro-
grammed or erased. After a sector is protected, it cannot be unprotected by user code. The
Flash Sector Protect Register is cleared after reset, and any previously-written protection
values are lost. User code must write this register in their initialization routine if they pre-
fer to enable sector protection.
The Flash Sector Protect Register shares its Register File address with the Page Select
Register. The Flash Sector Protect Register is accessed by writing the Flash Control Regis-
FWP Flash Code Protection Description
0
1
Table 79. Flash Code Protection Using the Flash Option Bits
95H
Programming and erasing disabled for all of Flash Program Mem-
ory. In user code programming, Page Erase and Mass Erase are all
disabled. Mass Erase is available through the On-Chip Debugger.
Programming, Page Erase and Mass Erase are enabled for all of
Flash Program Memory.
causes a Page Erase only if the active page resides in a sector that is not pro-
Figure 22
on page 148 for details.
P R E L I M I N A R Y
73H
and
8CH
, sequentially. The Page Select Regis-
Z8 Encore! XP
Product Specification
Table 78
®
F082A Series
on page
Operation
150