Z8FMC04100 ZILOG [Zilog, Inc.], Z8FMC04100 Datasheet - Page 86

• Manufacturer Part Number: Z8FMC04100
• Description: Z8 Encore-R Motor Control Flash MCUs
• Manufacturer: ZILOG [Zilog, Inc.]

64
Z8 Encore!
Product Specification
Watch-Dog Timer
Watch-Dog Timer Refresh
Watch-Dog Timer Time-Out Response
®
Motor Control Flash MCUs
Table 39. Watch-Dog Timer Approximate Time-Out Delays
When first enabled, the Watch-Dog Timer is loaded with the value in the Watch-Dog
Timer Reload registers. The Watch-Dog Timer then counts down to
instruction is executed by the eZ8 CPU. Execution of the
counter to be reloaded with the WDT Reload value stored in the Watch-Dog Timer Reload
registers. Counting resumes following the reload operation.
When the Z8FMC16100 Series Flash MCU is operating in DEBUG Mode (through the
On-Chip Debugger), the Watch-Dog Timer is continuously refreshed to prevent spurious
Watch-Dog Timer time-outs.
The Watch-Dog Timer times out when the counter reaches
Watch-Dog Timer generates either a system exception or a Reset. The
Bit determines the time-out response of the Watch-Dog Timer. Refer to the Option Bits
chapter for information regarding programming of the
WDT System Exception in Normal Operation
If configured to generate a system exception when a time-out occurs, the Watch-Dog
Timer issues an exception request to the interrupt controller. The eZ8 CPU responds to the
request by fetching the System Exception vector and executing code from the vector
address. After time-out and system exception generation, the Watch-Dog Timer is
reloaded automatically and continues counting.
WDT System Exception in Stop Mode
If configured to generate a system exception when a time-out occurs and the
Z8FMC16100 Series Flash MCU is in STOP mode, the Watch-Dog Timer automatically
initiates a Stop-Mode Recovery and generates a system exception request. Both the WDT
status bit and the STOP bit in the
set to 1 following WDT time-out in STOP mode. Refer to the
Recovery
WDT Reload
Value (Hex)
FFFF
0400
chapter on page 23 for more information.
WDT Reload
(Decimal)
65,536
Value
1024
P R E L I M I N A R Y
Reset Status and Control Register
Typical
(with 10 KHz Typical WDT Oscillator Frequency)
102 ms
6.55 s
Approximate Time-Out Delay
Description
Reset default value time-out delay.
Maximum time-out delay.
WDT_RES
WDT
0000h
instruction causes the down-
Reset and Stop-Mode
Option Bit.
. A time-out of the
section on page 29 are
0000h
WDT_RES
PS024604-1005
unless a
Option
WDT