Aaeon PCM-5894 Manual page 28

J2 is used to sychronize the system clock with the CPU clock and
PCI clock. You may need to adjust the CPU clock according to the
base CPU speed.
CPU clock setting
PCI
27.5MHz
32MHz
33.3MHz
25MHZ
30MHz
33MHz
32MHz
* default setting
18 PCM-5894/5892 User Manual
J2
1 3 5
2 4 6
1 3 5
2 4 6
1 3 5
2 4 6
1 3 5
2 4 6
1 3 5
2 4 6
1 3 5
*
2 4 6
1 3 5
2 4 6
CPU
55MHz
75MHz
50MHz
50MHz
60MHz
66MHz
40MHz