6 program example for watchdog timer, Program example for watchdog timer – FUJITSU F2MC-8L F202RA User Manual
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CHAPTER 6 WATCHDOG TIMER
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
0009H
;
Address of watchdog control register
WDT_CLR EQU 00000101B
VECT
DSEG
ABS
;
[DATA SEGMENT]
ORG
0FFFEH
RST_V DW
PROG
;
Setting reset vector
VECT
ENDS
;------------------------Main program---------------------------------------------------------------------------------
CSEG
;
[CODE SEGMENT]
PROG
;
Initialization routine upon reset
MOVW
SP,#0280H
;
Setting initial value of stack pointer (for interrupt)
:
Initializing interrupt or other peripheral functions
:
INIT
MOV
WDTC,#WDT_CLR
;
Activating watchdog timer
MAIN
MOV
WDTC,#WDT_CLR
;
Clearing watchdog timer
:
User processing (interrupt may occur in this processing.)
:
JMP
MAIN
;
Ensure that the time necessary for running the loop is
shorter than the minimum time interval of the watchdog
timer.
ENDS
;---------------------------------------------------------------------------------------------------------------------
END