Z8F0823PJ005SG Zilog, Z8F0823PJ005SG Datasheet - Page 99

• Manufacturer Part Number: Z8F0823PJ005SG
• Description: IC ENCORE MCU FLASH 8K 28-DIP
• Manufacturer: Zilog
• Series: Encore!® XP®r

Specifications of Z8F0823PJ005SG

• Core Processor: Z8
• Core Size: 8-Bit
• Speed: 5MHz
• Connectivity: IrDA, UART/USART
• Peripherals: Brown-out Detect/Reset, LED, POR, PWM, WDT
• Number Of I /o: 22
• Program Memory Size: 8KB (8K x 8)
• Program Memory Type: FLASH
• Ram Size: 1K x 8
• Voltage - Supply (vcc/vdd): 2.7 V ~ 3.6 V
• Data Converters: A/D 8x10b
• Oscillator Type: Internal
• Operating Temperature: 0°C ~ 70°C
• Package / Case: 28-DIP (0.600", 15.24mm)
• Lead Free Status / RoHS Status: Lead free / RoHS Compliant
• Eeprom Size: -
• Other names: 269-4218; Z8F0823PJ005SG

PS025203-0405
WDT Reload Value
FFFFFF
000004
Watch-Dog Timer Refresh
Watch-Dog Timer Time-Out Response
(Hex)
When first enabled, the Watch-Dog Timer is loaded with the value in the Watch-Dog
Timer Reload registers. The Watch-Dog Timer counts down to
instruction is executed by the eZ8 CPU. Execution of the WDT instruction causes the
downcounter to be reloaded with the WDT Reload value stored in the Watch-Dog Timer
Reload registers. Counting resumes following the reload operation.
When the Z8 Encore!
On-Chip Debugger), the Watch-Dog Timer is continuously refreshed to prevent any
Watch-Dog Timer time-outs.
The Watch-Dog Timer times out when the counter reaches
Watch-Dog Timer generates either an interrupt or a system reset. The WDT_RES Flash
Option Bit determines the time-out response of the Watch-Dog Timer. Refer to the chapter
“Flash Option Bits” on page 132
Flash Option Bit.
WDT Interrupt in Normal Operation
If configured to generate an interrupt when a time-out occurs, the Watch-Dog Timer issues
an interrupt request to the interrupt controller and sets the WDT status bit in the Watch-Dog
Timer Control register. If interrupts are enabled, the eZ8 CPU responds to the interrupt
request by fetching the Watch-Dog Timer interrupt vector and executing code from the
vector address. After time-out and interrupt generation, the Watch-Dog Timer counter
rolls over to its maximum value of
Timer counter is not automatically returned to its Reload Value.
The Reset Status Register (page 27) must be read before clearing the WDT interrupt. This
read clears the WDT timeout flag and prevents further WDT interrupts for immediately
occurring.
Table 57. Watch-Dog Timer Approximate Time-Out Delays
WDT Reload Value
16,777,215
(Decimal)
®
4
Z8F0823 Series devices are operating in DEBUG Mode (using the
P R E L I M I N A R Y
for information regarding programming of the WDT_RES
FFFFFH
(with 10KHz typical WDT oscillator frequency)
28 minutes
Typical
400 µs
and continues counting. The Watch-Dog
Approximate Time-Out Delay
Z8 Encore!
000000H
000000H
Minimum time-out delay
Maximum time-out delay
Product Specification
. A time-out of the
®
Description
Z8F0823 Series
unless a WDT
Watch-Dog Timer
82