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Timeout status & reset watchdog - index 3ch -15, Programming watchdog - basic operation -15 – Acrosser AR-B1320 User Manual

Page 34

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A

A

R

R

-

-

B

B

1

1

3

3

2

2

0

0

U

U

s

s

e

e

r

r

s

s

G

G

u

u

i

i

d

d

e

e

3-15

3.15.4

TIMEOUT STATUS & RESET WATCHDOG - INDEX 3CH

0: Timer timeout not happened

Bit 7(read only)

1: Timer timeout happened

Bit 6

Write this bit “1” to reset timer

Bit 0-5

The value on this bit has no meaning.
Other function. Please do not modify these
bits.

3.15.5 PROGRAMMING WATCHDOG - BASIC OPERATION

If you would like to access the M6117C configuration register, you need to unlock the register at
first and lock it again after finishing the operation.

(1) Unlock Configuration Register

Mov al,

13h

Out 22h,

al

Nop
Nop
Mov al,

0c5h

Out 23h,

al

Nop
Nop

(2) Lock Configuration Register

Mov al,

13h

Out 22h,

al

Nop
Nop
Mov al,

00h

Out 23h,

al

Nop
Nop

(3) Read the Value in the Configuration Register

Example 1: Read data from INDEX 3Ch

Unlock_Cfg_Reg

;Unlock configuration register

Mov

al, 3ch

;Points to index 3ch

Out 22h,

al

Nop

Nop

In

al, 23h

;Read out

Nop

Nop

Push

ax

;Save to stack

Lock_Cfg_Reg

;Lock configuration register

Pop

ax

;Restore ax and result in al register