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12.3 Multifunctional Timer Registers
Table 12.3-2 Functions of Bits for Timer Control Status Register (Lower) (TCCS)
Bit name
Function
bit7
IVF:
Free-running timer
interrupt request flag
bit
This bit is a flag that requests an interrupt.
When an overflow of the counter value of the 16-bit free-running timer
occurs, "1" is set.
When this bit is set to "1" while the free-running timer interrupt enable bit
(IVFE) is "1", an interrupt request is output.
If this bit is "0", an interrupt request is cleared.
If this bit is "1", operation is not affected.
A read-modify-write instruction always reads "1" from this bit.
bit6
IVFE:
Free-running timer
interrupt request
enable bit
This bit enables an interrupt request.
When the free-running timer interrupt request flag bit (IVF) is set to "1" while
this bit is "1", an interrupt request is output.
bit5
STOP:
Count stop bit
This bit is used to stop the 16-bit free-running timer from counting.
If this bit is "0", the counter of the 16-bit free-running timer is started.
If this bit is "1", the counter of the 16-bit free-running timer is stopped.
Note:
When the counter of the 16-bit free-running timer stops, the output
compare operation also stops.
bit4
MODE:
Free-running timer
initialization condition
setting bit
This bit sets the initialization condition for the counter value of the 16-bit
free-running timer.
If "0" is set, the counter value is cleared to "0000H" by reset and clear bit
(SCLR="1").
If "1" is set, the counter value is cleared to "0000H" by a match of the
counter value and the compare clear register (CPCLR) value of the 16-bit
free-running timer, in addition to reset and clear bit (SCLR="1").
Note:
The counter value after detecting the initialization condition set to the
MODE bit is cleared.
bit3
SCLR:
Clear bit
This bit is used to clear the counter value to "0000H" during operation of the
counter of the 16-bit free-running timer.
If this bit is "0", operation is not affected.
If this bit is "1", the counter value is cleared to "0000H". The read value is
always "0".
Note:
To clear the counter value to "0000H" while the counter of the 16-bit free-
running timer is stopped (STOP="1"), set "0000H" to the timer data
register (TCDT).
bit2
bit1
bit0
CLK2, CLK1, CLK0:
Count clock setting bit
These bits are used to set the count clock of the 16-bit free-running timer.
The count clock is changed immediately after these bits are set. Therefore,
set these bits while the output compare and input capture units are stopped.