Program Example For Watchdog Timer; Programming Examples Of Watchdog Timer - Fujitsu F2MC-8L F202RA Hardware Manual

6.6

Program Example for Watchdog Timer

Programming examples for the watchdog timer are provided below.
■

Programming Examples of Watchdog Timer

● Processing specification
• Activate the watchdog timer immediately after the program starts.
• Clear the watchdog timer whenever the loop of the main program is run.
• Ensure that the time necessary for running the main loop once, including interrupt handling, is shorter
than the minimum time interval (approximately 335.5 ms: operating at 12.5 MHz) of the watchdog
timer.
● Coding example
WDTC EQU
WDT_CLR EQU 00000101B
VECT
RST_V DW
VECT
;------------------------Main program---------------------------------------------------------------------------------
PROG
INIT
MAIN
;---------------------------------------------------------------------------------------------------------------------
0009H
DSEG ABS
ORG 0FFFEH
PROG
ENDS
CSEG
MOVW SP,#0280H
:
Initializing interrupt or other peripheral functions
:
MOV WDTC,#WDT_CLR
MOV WDTC,#WDT_CLR
:
User processing (interrupt may occur in this processing.)
:
JMP MAIN
ENDS
END
CHAPTER 6 WATCHDOG TIMER
; Address of watchdog control register
; [DATA SEGMENT]
; Setting reset vector
; [CODE SEGMENT]
; Initialization routine upon reset
; Setting initial value of stack pointer (for interrupt)
; Activating watchdog timer
; Clearing watchdog timer
; Ensure that the time necessary for running the loop is
shorter than the minimum time interval of the watchdog
timer.
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