REFERENCE FREQUENCY COUNTER
IDENTIFIER = 0
REFERENCE
FREQUENCY
SELECT
REFERENCE
FREQUENCY
COUNTER
DIVIDE RATIO
REFERENCE
FREQUENCY
SELECT
AUX
Din
0
REF
Tx–0
Rx–0
ENABLE SELECT SELECT
12–BITS REF FREQ
DATA
fR1
S1
fR1
S2
AUX REFERENCE
FREQUENCY COUNTER
DIVIDE RATIO
14–BITS AUX REF FREQ
DATA
CLK
ENB
NOTE: ENB must be high during the serial transfer.
Figure 9. Programming Format of the Auxiliary/Reference Frequency Counters
Din
MCU
USING
CLK
SERIAL PERIPHERAL
INTERFACE PORT
ENB
UNIVERSAL PLL
AUX DATA BIT = 0
Figure 10. MCU Interface Using SPI
ADin
MCU
Din
USING
NORMAL I/O PORT
CLK
ENB
UNIVERSAL PLL
AUX DATA BIT = 1
Figure 11. MCU Interface Using Normal I/O Ports with
Both Din and ADin for Faster Programming Time
MOTOROLA
MC145162•MC145162–1
9