ez80f92 ZiLOG Semiconductor, ez80f92 Datasheet - Page 79

• Manufacturer Part Number: ez80f92
• Description: Ez80acclaim Flash Microcontrollers
• Manufacturer: ZiLOG Semiconductor

Watchdog Timer
PS015313-0508
Watchdog Timer Overview
The Watchdog Timer (WDT) helps protect against corrupt or unreliable software, power
faults, and other system-level problems which may place the CPU into unsuitable
operating states.
The eZ80F92 WDT features:
•
•
•
•
Figure 19
System Clock
Four programmable time-out periods: 2
Two selectable WDT clock sources: the system clock or the Real-Time Clock source
(on-chip 32 kHz crystal oscillator or 50/60 Hz signal)
A selectable time-out response: a time-out can be configured to generate either a
RESET or a nonmaskable interrupt (NMI)
A WDT time-out RESET indicator flag
RTC Clock
displays the block diagram for the Watchdog Timer.
WDT_CLK
Figure 19. Watchdog Timer Block Diagram
Time-out Compare Logic
(WDT_PERIOD)
Upcounter
28-Bit
18
, 2
22
, 2
25
, and 2
27
clock cycles
Product Specification
RESET
NMI to eZ80 CPU
WDT Control Logic
Control Register/
Reset Register
eZ80F92/eZ80F93
Data[7:0]
Watchdog Timer
72