T89C51CC01 Atmel, T89C51CC01 Datasheet - Page 76

• Manufacturer Part Number: T89C51CC01
• Description: Enhanced 8-Bit Microcontroller
• Manufacturer: Atmel

Watchdog Programming
76
T89C51CC01
The three lower bits (S0, S1, S2) located into WDTPRG register permit to program the
WDT duration.
Table 52. Machine Cycle Count
To compute WD Time-Out, the following formula is applied:
Note:
The following table outlines the time-out value for Fosc
Table 53. Time-Out Computation
S2
0
0
0
0
1
1
1
1
S2
0
0
0
0
1
1
1
1
Svalue represents the decimal value of (S2 S1 S0)
S1
0
0
1
1
0
0
1
1
S1
0
0
1
1
0
0
1
1
FTime Out
S0
0
1
0
1
0
1
0
1
–
=
S0
0
1
0
1
0
1
0
1
---------------------------------------------------------------- -
12
Fosc = 12 MHz
131.07 ms
262.14 ms
524.29 ms
16.38 ms
32.77 ms
65.54 ms
×
1.05 s
2.10 s
(
(
2
14
F
×
wd
2
Svalue
XTAL
Fosc = 16 MHz
Machine Cycle Count
) 1
196.56 ms
393.12 ms
786.24 ms
12.28 ms
24.57 ms
49.14 ms
98.28 ms
–
1.57 s
= 12 MHz in X1 mode
)
2
2
2
2
2
2
2
2
14
15
16
17
18
19
20
21
- 1
- 1
- 1
- 1
- 1
- 1
- 1
- 1
Fosc = 20 MHz
4129K–CAN–01/05
157.28 ms
314.56 ms
629.12 ms
19.66 ms
39.32 ms
78.64 ms
9.82 ms
1.25 s