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Table 3-3 . watchdog timeout period selection -20, Maxq610 user’s guide, Table 3-3. watchdog timeout period selection – Maxim Integrated MAXQ610 User Manual

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3-20

MAXQ610 User’s Guide

The watchdog timeout selection is made using bits WD1 (WDCN .5) and WD0 (WDCN .4) . The watchdog has four time-
out selections based on the system clock frequency as shown Figure 3-1 . Because the timeout is a function of the
system clock, the actual timeout interval is dependent on both the crystal frequency and the system clock mode selec-
tion . Table 3-3 shows a summary of the selectable watchdog timeout intervals for the various system clock modes and
WD[1:0] control bit settings . If enabled, the watchdog reset is always scheduled to occur 512 system clocks following
the timeout . Watchdog-generated resets last for eight system clock cycles .

Table 3-3. Watchdog Timeout Period Selection

SYSTEM CLOCK

MODE

SYSTEM CLOCK SELECT BITS

WATCHDOG TIMEOUT

(IN NUMBER OF OSCILLATOR CLOCKS)

PMME

CD1

CD0

WD[1:0] = 00b

WD[1:0] = 01b

WD[1:0] = 10b

WD[1:0] = 11b

Divide by 1 (default)

0

0

0

2

15

2

18

2

21

2

24

Divide by 2

0

0

1

2

16

2

19

2

22

2

25

Divide by 4

0

1

0

2

17

2

20

2

23

2

26

Divide by 8

0

1

1

2

18

2

21

2

24

2

27

Power-Management
Mode (Divide by 256)

1

x

x

2

23

2

26

2

29

2

32