Z8F0412SJ020SG Zilog, Z8F0412SJ020SG Datasheet - Page 169

• Manufacturer Part Number: Z8F0412SJ020SG
• Description: IC ENCORE MCU FLASH 4K 28SOIC
• Manufacturer: Zilog
• Series: Encore!® XP®r

Specifications of Z8F0412SJ020SG

• Core Processor: Z8
• Core Size: 8-Bit
• Speed: 20MHz
• Connectivity: I²C, IrDA, SPI, UART/USART
• Peripherals: Brown-out Detect/Reset, POR, PWM, WDT
• Number Of I /o: 19
• Program Memory Size: 4KB (4K x 8)
• Program Memory Type: FLASH
• Ram Size: 1K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 3.6 V
• Oscillator Type: Internal
• Operating Temperature: 0°C ~ 70°C
• Package / Case: 28-SOIC (7.5mm Width)
• Processor Series: Z8F041xx
• Core: eZ8
• Data Bus Width: 8 bit
• Data Ram Size: 1 KB
• Interface Type: I2C, SPI, UART
• Maximum Clock Frequency: 20 MHz
• Number Of Programmable I/os: 19
• Number Of Timers: 2
• Operating Supply Voltage: 2.7 V to 3.6 V
• Maximum Operating Temperature: + 70 C
• Mounting Style: SMD/SMT
• Minimum Operating Temperature: 0 C
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Data Converters: -
• Lead Free Status / Rohs Status: Details
• Other names: 269-4107; Z8F0412SJ020SG

PS022517-0508
Flash Read Protection
Flash Write/Erase Protection
The user code contained within the Flash memory can be protected from external access.
Programming the Flash Read Protect Option Bit prevents reading of user code by the
OCD or by using the Flash Controller Bypass mode. For more information, see
Bits
Z8 Encore! XP
gram and erasure of the Flash memory contents. This protection is provided by the Flash
Controller unlock mechanism, the Flash Sector Protect Register, and the Flash Write Pro-
tect option bit.
Flash Controller Unlock Mechanism
At Reset, the Flash Controller locks to prevent accidental program or erasure of the Flash
memory. To program or erase the Flash memory, the Flash controller must be unlocked.
After unlocking the Flash Controller, the Flash can be programmed or erased. Any value
written by user code to the Flash Control Register or Page Select Register out of sequence
locks the Flash Controller.
Follow the steps below to unlock the Flash Controller from user code:
1. Write
2. Write the page to be programmed or erased to the Page Select Register.
3. Write the first unlock command
4. Write the second unlock command
5. Re-write the page written in
Flash Sector Protection
The Flash Sector Protect Register is configured to prevent sectors from being programmed
or erased. Once 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
is lost. User code must write this register in the initialization routine if enable sector
protection is desired.
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
Register with
at the Page Select Register address. When the user code writes the Flash Sector Protect
Register, bits can only be set to 1. Sectors can be protected, but not unprotected, using reg-
ister write operations. Writing a value other than
lects the Flash Sector Protect Register and re-enables access to the Page Select Register.
on page 163 and
00H
5EH
®
to the Flash Control Register to reset the Flash Controller.
F0822 Series provides several levels of protection against accidental pro-
. After the Flash Sector Protect Register is selected, it can be accessed
On-Chip Debugger
step 2
73H
to the Page Select Register.
8CH
to the Flash Control Register.
on page 171.
to the Flash Control Register.
5EH
to the Flash Control Register dese-
Z8 Encore! XP
Product Specification
®
F0822 Series
Flash Memory
Option
156