z8f0813 ZiLOG Semiconductor, z8f0813 Datasheet - Page 35

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

PS024314-0308
Internal RESET
System Clock
Note: Not to Scale
WDT Clock
V
CC
signal
Watchdog Timer Reset
External Reset Input
= 3.3 V
V
V
POR
VBO
The POR level is greater than the VBO level by the specified hysteresis value. This
ensures that the device undergoes a POR after recovering from a VBO condition.
If the device is in NORMAL or STOP mode, the Watchdog Timer can initiate a System
Reset at time-out if the WDT_RES Flash Option Bit is programmed to 1. This is the
unprogrammed state of the WDT_RES Flash Option Bit. If the bit is programmed to 0, it
configures the Watchdog Timer to cause an interrupt, not a System Reset, at time-out.
The WDT status bit in the WDT Control register is set to signify that the reset was
initiated by the Watchdog Timer.
The RESET pin has a Schmitt-Triggered input and an internal pull-up resistor. Once the
RESET pin is asserted for a minimum of four system clock cycles, the device progresses
through the System Reset sequence. Because of the possible asynchronicity of the system
Execution
Program
Figure 6. Voltage Brownout Reset Operation
Brownout
Voltage
counter delay
POR
Z8 Encore! XP
Reset and Stop Mode Recovery
Product Specification
Execution
Program
®
F0823 Series
V
CC
= 3.3 V
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