
Rev.3.02
Apr 10, 2008
REJ03B0177-0302
38D2 Group
Oscillation External Output Function
The 38D2 group has the oscillation external output function to
output the rectangular waveform of the clock obtained by the
oscillation circuits from P41 and P40.
In order to validate the oscillation external output function, set
P40 or P41, or both to the output mode (set the corresponding
direction register to “1”).
The level of the XCOUT external output signal becomes “H” by
the P40/P41 oscillation output control bits (bits 0 and 1) of the
oscillation output control register (address 001016) in the
following states;
the function to output the signal from the XCOUT pin externally
is selected
the sub clock (XCIN
XCOUT) is in the stop oscillating or stop
mode.
Likewise, the level of the XOUT external output signal becomes
“H” by the P40/P41 oscillation output control bits (bits 0 and 1)
of the oscillation output control register (address 001016) in the
following states;
the function to output the signal from the XOUT pin externally
is selected
the main clock (XIN
XOUT) is in the stop oscillating or stop
mode.
<Note>
When the signal from the XOUT pin or XCOUT pin of the
oscillation circuit is input directly to the circuit except this MCU
and used, the system operation may be unstabilized.
In order to share the oscillation circuit safely, use the clock
output from P40 and P41 by this function for the circuits except
this MCU.
Fig. 63 Structure of oscillation output control register
Fig. 64 Block diagram of oscillation external output function
b7
Oscillation output control register
(OSCOUT : address 001016)
P40/P41 oscillation output control bits
b1 b0
0 0 : P41, P40 = Normal port
0 1 : P41 = Normal port, P40 = XOUT
1 0 : P41 = Normal port, P40 = XCOUT
1 1 : P41 = XCOUT , P40 = XOUT
Not used (Do not write to “1”.)
b0
STP instruction
S
R
Q
XIN
XOUT
Interrupt request
Interrupt disable flag I
Reset
XIN-XOUT oscillation stop bit
(CPUM Bit 5)
P61/XCIN
P62/XCOUT
Port XC switch bit
(CPUM Bit 4)
P41/OOUT1
P40/OOUT0
P41 direction register
P40 direction register
OSCOUT control
P41 output latch
P40 output latch
Oscillation
output
selection
circuit