42
SINGLE-CHIP 8-BIT CMOS MICROCOMPUTER
3827 Group
MITSUBISHI MICROCOMPUTERS
T
OUT
/
φ
CLOCK OUTPUT FUNCTION
The internal system clock
φ
or timer 2 divided by 2 (T
OUT
output)
can be output from port P4
3
by setting the T
OUT
/
φ
output control
bit (bit 1) of the timer 123 mode register and the T
OUT
/
φ
output
control register. Set bit 3 of the port P4 direction register to “1”
when outputting the clock.
Fig. 47 Structure of T
OUT
/
φ
output-related register
T
OUT
/
φ
output control bit
0 :
φ
clock output
1 : T
OUT
output
Not used (return “0” when read)
T
OUT
/
φ
output control register
(CKOUT : address 002A
16
)
b7
b0
Timer 123 mode register
(T123M : address 0029
16
)
T
OUT
output active edge switch bit
0 : Start on “H” output
1 : Start on “L” output
T
OUT
/
φ
output control bit
0 : T
OUT
/
φ
output disable
1 : T
OUT
/
φ
output enable
Timer 2 write control bit
0 : Write data in latch and timer
1 : Write data in latch only
Timer 2 count source selection bit
0 : Timer 1 output
1 : f(X
IN
)/16
(or f(X
CIN
)/16 in low-speed mode
8
)
Timer 3 count source selection bit
0 : Timer 1 output
1 : f(X
IN
)/16
(or f(X
CIN
)/16 in low-speed mode
8
)
Timer 1 count source selection bit
0 : f(X
IN
)/16
(or f(X
CIN
)/16 in low-speed mode
8
)
1 : f(X
CIN
)
Not used (return “0” when read)
8
: Internal clock
φ
is f(X
CIN
)/2 in low-speed mode.
b7
b0