Z8F041APH020SG2156 ZiLOG, Z8F041APH020SG2156 Datasheet - Page 110

• 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

Watchdog Timer
PS022827-1212
WDT Reload Value
Operation
FFFFFF
000004
(Hex)
The Watchdog Timer (WDT) protects against corrupt or unreliable software, power faults
and other system-level problems which may place the Z8 Encore! XP F082A Series
devices into unsuitable operating states. The features of Watchdog Timer include:
•
•
•
The Watchdog Timer is a one-shot timer that resets or interrupts the Z8 Encore! XP F082A
Series devices when the WDT reaches its terminal count. The Watchdog Timer uses a ded-
icated on-chip RC oscillator as its clock source. The Watchdog Timer operates in only two
modes: ON and OFF. Once enabled, it always counts and must be refreshed to prevent a
time-out. Perform an enable by executing the WDT instruction or by setting the WDT_AO
Flash option bit. The WDT_AO bit forces the Watchdog Timer to operate immediately
upon reset, even if a WDT instruction has not been executed.
The Watchdog Timer is a 24-bit reloadable downcounter that uses three 8-bit registers in
the eZ8 CPU register space to set the reload value. The nominal WDT time-out period is
described by the following equation:
where the WDT reload value is the decimal value of the 24-bit value given by
{WDTU[7:0], WDTH[7:0], WDTL[7:0]} and the typical Watchdog Timer RC oscillator
frequency is 10 kHz. The Watchdog Timer cannot be refreshed after it reaches
The WDT reload value must not be set to values below
mation about approximate time-out delays for the minimum and maximum WDT reload
values.
WDT Time-out Period (ms)
On-chip RC oscillator
A selectable time-out response: reset or interrupt
24-bit programmable time-out value
Table 58. Watchdog Timer Approximate Time-Out Delays
WDT Reload Value
16,777,215
(Decimal)
4
P R E L I M I N A R Y
=
WDT Reload Value
------------------------------------------
(with 10 kHz typical WDT oscillator frequency)
10
28 minutes
Typical
400 s
Approximate Time-Out Delay
Z8 Encore! XP
000004H
Minimum time-out delay
Maximum time-out delay
Product Specification
. Table 58 provides infor-
Description
®
Watchdog Timer
F082A Series
000002H
.
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