Table 4-8 System Frequencies from 32.768-kHz Reference
To obtain clock frequency in kilohertz, find counter modulus in the left column, then look in appropriate prescaler cell.
Shaded cells contain values that exceed specified maximum system frequency.
Modulus
Y
Prescaler
[W:X] = 00
131
[W:X] = 01
262
[W:X] = 10
524
[W:X] = 11
1049
000000
000001
000010
000011
000100
000101
000110
000111
001000
001001
001010
001011
001100
001101
001110
001111
010000
010001
010010
010011
010100
010101
010110
010111
011000
011001
011010
011011
011100
011101
011110
011111
100000
100001
100010
100011
100100
100101
100110
100111
101000
101001
101010
101011
101100
262
524
1049
2097
393
786
1573
3146
524
1049
1311
1573
1835
2097
2359
2621
2884
3146
3408
3670
3932
4194
4456
4719
4981
5243
5505
5767
6029
6291
6554
6816
7078
7340
7602
7864
8126
8389
8651
8913
9175
9437
9699
9961
10224
10486
10748
11010
11272
11534
11796
2097
4194
655
2621
5243
786
3146
6291
918
3670
7340
1049
1180
1311
1442
1573
1704
1835
1966
2097
2228
2359
2490
2621
2753
2884
3015
3146
3277
3408
3539
3670
3801
3932
4063
4194
4325
4456
4588
4719
4850
4981
5112
5243
5374
5505
5636
5767
5898
4194
8389
4719
9437
5243
10486
11534
12583
13631
14680
15729
16777
17826
18874
19923
20972
22020
23069
24117
25166
26214
27263
28312
29360
30409
31457
32506
33554
34603
35652
36700
37749
38797
39846
40894
41943
42992
44040
45089
46137
47186
5767
6291
6816
7340
7864
4
8389
8913
9437
9961
10486
11010
11534
12059
12583
13107
13631
14156
14680
15204
15729
16253
16777
17302
17826
18350
18874
19399
19923
20447
20972
21496
22020
22544
23069
23593
MOTOROLA
4-14
SYSTEM INTEGRATION MODULE
MC68331
USER’S MANUAL
MOTOROLA [ MOTOROLA ]
