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C. watchdog timer configuration – IBASE IB530 User Manual

Page 53

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APPENDIX

IB530F User’s Manual

49

C. Watchdog Timer Configuration


The WDT is used to generate a variety of output signals after a user
programmable count. The WDT is suitable for use in the prevention of
system lock-up, such as when software becomes trapped in a deadlock.
Under these sort of circumstances, the timer will count to zero and the
selected outputs will be driven. Under normal circumstance, the user
will restart the WDT at regular intervals before the timer counts to zero.

SAMPLE CODE:
This code and information is provided "as is" without warranty of any
kind, either expressed or implied, including but not limited to the
implied warranties of merchantability and/or fitness for a particular
purpose.

;[]================================================
; Name

: Enable_And_Set_Watchdog

; IN : AL - 1sec ~ 255sec
; OUT

: None

;[]================================================
Enable_And_Set_Watchdog Proc

Near

push

ax

;save

time

interval

call

Unlock_Chip


mov

cl,

2Bh

call

Read_Reg

and al, NOT 10h

call

Write_Reg

;set

GP24

as

WDTO


mov

cl,

07h

mov

al,

08h

call

Write_Reg

;switch

to

LD8

mov

cl,

0F5h

call

Read_Reg

and al, NOT 08h

call Write_Reg

;set count mode as second

pop

ax

mov

cl,

0F6h

call

Write_Reg

;set

watchdog

timer


mov

al,

01h

mov

cl,

30h

call

Write_Reg

;watchdog

enabled