Acrosser AR-B9612 - Manual (Page 30)

AR-B9612 User’s Guide
3-11
3.2.7 CPU Base Clock Select (JP1)
This board provides three types of CPU clock for selecting, there
is 25MHz, 33MHz, & 40MHz for choice.
The CPU input clock is twice of operation clock.
CPU Input Clock CPU Operation Clock
50MHz 25MHz
66.6MHz 33.3MHz
80MHz 40MHz
Table 3-2 CPU Clock
1
2
3
4
50MHz
1
2
3
4
66.6MHz
Factory Presetting
1
2
3
4
80MHz
Figure 3-11 JP1 : CPU Base Clock
NOTE : The frequency of input clock is selected by JP1, it is
twice of CPU clock. For example, If 33MHz CPUs
used, the OSC1 clock will be 66MHz.