ZiLOG Z8 - Page 218

Z8 Microcontrollers
Instruction Descriptions and Formats ZiLOG
12-78 UM001601-0803
WDT
WATCH-DOG TIMER
WDT
Watch-Dog Timer
WDT
Instruction Format:
Operation:
The WDT (Watch-Dog Timer) is a retriggerable one shot timer that will reset the Z8 if it reaches its terminal count.
The WDT is initially enabled by executing the WDT instruction. Each subsequent execution of the WDT instruction
refreshes the timer and prevents the WDT from timing out.
Note:
The WDT instruction should not be used following any instruction in which the condition of the flags is important.
Example:
If the WDT is enabled, the statement:
WDT
Op Code: .BYTE 5FH
refreshes the Watch-Dog Timer.
Example:
The first execution of the statement:
WDT
Op Code: .BYTE 5FH
enables the Watch-Dog Timer.
Flags: C: Unaffected
Z: Undefined
S: Undefined
V: Undefined
D: Unaffected
H: Unaffected