UPD784915B Datasheet, PDF (48/86 Pages) NEC – 16-BIT SINGLE-CHIP MICROCONTROLLERS

µPD784915B, 784916B
3.11 Clock Output Function
The µPD784916A can output a square wave (with a duty factor of 50%) to the P60/CLO pin as the operating clock
for the peripheral devices or other microccontrollers. To enable or disable the clock output, and to set the frequency
of the clock, the clock output mode register (CLOM) is used.
When setting the frequency, the division ratio can be set to fCLK/n (where n = 2, 4, 8, or 16) (fCLK = fOSC/2: fOSC is
the oscillation frequency of the oscillator).
Figure 3-26 shows the configuration of the clock output circuit.
The clock output (CLO) pin is shared with P60.
Figure 3-26. Block Diagram of Clock Output Circuit
CLOM 0 0 0 ENCLO 0 0 SELFRQ1 SELFRQ0
fCLK
fCLK/2
fCLK/4
fCLK/8
1/2
P60/CLO
P60
RESET
Remark fCLK: internal system clock
Caution Do not use the clock output function in the STOP mode. Clear ENCLO (CLOM.4) to 0 in the STOP
mode.
Figure 3-27 Application Example of Clock Output Function
µ PD784916B
µ PD75356
24
System clock
CLO
CL1
SCK1
SCK
SI1
SO
SO1
SI
LCD
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