ADLINK ACL-8454/12 User Manual
Page 20
12
• Installation & Configurations
CLOCK1 (High Frequency)
The clock source of CLOCK1 can be set by jumper ‘CLOCK1’. The
frequency could be 10 MHz or 2 MHz. Figure 2.5 shows the jumper setting
and the corresponding frequency. The default setting of CLOCK1 is using 2
MHz.
10M
CLOCK1= 2 MHz
CLOCK1
2M
10M
CLOCK1= 10 MHz
CLOCK1
2M
(Default)
Figure 2.5 Jumper setting of CLOCK1
CLOCK2 (Low Frequency)
The clock source of CLOCK2 can be set by jumper ‘CLOCK2’. The
frequency could be 1 MHz or 100 KHz which are divided from CLOCK1.
The CLOCK2 is provided for low frequency applications. Figure 2.6 shows
the jumper setting and the corresponding frequency. The default setting of
CLOCK2 is using 100 KHz.
1M
CLOCK2= 100 KHz
CLOCK2
100K
1M
CLOCK2= 1 MHz
CLOCK2
100K
(Default)
Figure 2.6 Jumper setting of CLOCK2
If user‘s application need a clock frequency lower than 100 KHz, the first
method is to use external clock source, the second method is to use one
counter to generate a frequency lower than 100 Khz then cascaded the low
frequency signal to the other counter’s clock source. This cascaded
counter configuration is feasible on the ACL-8454 by jumper setting. See
the next section for details of how to set cascaded counter.