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User’s Manual U12697EJ3V0UM
CHAPTER 19 CLOCK OUTPUT FUNCTION
19.1 Functions
The clock output function is used to output the clock supplied to a peripheral LSI and carrier output during remote
transmission. The clock selected by means of the clock output control register (CKS) is output from the PCL/P23 pin.
To output the clock pulse, follow the procedure described below.
<1>
Select the output frequency of the clock pulse (while clock pulse output is disabled) with bits 0 to 3 (CCS0 to
CCS3).
<2>
Set 0 in output latch P23.
<3>
Set bit 3 (PM23) of the port mode register (PM2) to 0 (to set the output mode).
<4>
Set bit 4 (CLOE) of CKS to 1.
Caution If the output latch of P23 is set to 1, clock output cannot be used.
Remark
The clock output function is designed so that pulses with a narrow width are not output when clock output
enable/disabled is switched (See “
*
” in
Figure 19-1
).
Figure 19-1. Remote Control Output Application Example
CLOE
PCL/P23 pin output
*
*
