Fujitsu MB15C02 4. Setting the Divide Ratio

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MB15C02
4. Setting the Divide Ratio
(1) Serial data format
The format of the serial data is shown is Figure 3. The serial data is composed of a control bit and divide ratio
setting data. The control bit selects the programmable divider or programmable reference divider.
In case of the programmable divider, serial data consists of 18 bits(6 bits for the s w allow counter and 12 bits f or the
programmable counter) and 1 control bit as shown in Figure 3.1. In case of the programmable reference divider,
the serial data consists of 14 divider bits and 1 control bit as shown in Figure 3.2.
The control bit is set to 0 to identify the serial data for the programmable divider and to 1 to select the serial data
for the programmable reference divider.
CA
0A 1A 2A 3A 4A 5N 0N 1N 2N 3N 4N 5N 6N 7N 8N 9N
10 N 11
Direction of data input
Figure 3. Serial data format
CR
0R 1R 2R 3R 4R 5R 6R 7R 8R 9R
10 R 11 R 12 R 13
Direction of data input
Figure 3.1. Divide ratio for the programmable divider
Figure 3.2. Divide ratio for the programmable reference divider
LSB MSB
Swallow counter Programmable counter
control bit
LSB MSB
control bit
Programmable reference counter