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CHAPTER 11 16-BIT RELOAD TIMER
Table 11.4-2 Function Description of Each Bit of the Low Part of the Timer Control StatusRegister
(TMCSR0/TMCSR1: L)
Bit name
Function
bit6
OUTE:
Timer output
enable bit
This bit enables or disables output to the timer output pin.
When this bit is set to "0", the pin serves as an I/O port. When this bit is set
to "1", the pin serves as a timer output pin.
bit5
OUTL:
Pin output level
setting bit
This bit selects the output level of the timer output pin.
The timer output pin outputs a toggle waveform in reload mode or a square
wave indicating that counting is in progress in one-shot mode.
Opposite output levels are output from the pin depending on whether this bit
is set to "0" or "1".
bit4
RELD:
Reload selection bit
This bit enables reloading.
When this bit is set to "1", the timer is in reload mode. When an underflow of
the 16-bit down counter occurs, the value stored in the 16-bit reload register
is loaded into the 16-bit down counter and counting continues.
When this bit is set to "0", the timer is in one-shot mode. When an underflow
of the 16-bit down counter occurs, counting stops.
bit3
INTE:
Underflow interrupt
request enable bit
This bit enables interrupt requests.
When this bit and the interrupt request flag (UF) bit are 1, the timer outputs
an interrupt request.
bit2
UF:
Underflow interrupt
request flag bit
This is a flag bit for an interrupt request.
This bit is set to "1" when an underflow of the 16-bit down counter occurs.
An interrupt request is output when this bit is set to "1" while the underflow
interrupt request enable bit (INTE) is set to "1".
Setting this bit to "0" clears an interrupt request.
Setting this bit to "1" has no effect on operation.
This bit is also cleared when EI2OS is activated.
bit1
CNTE:
Count enable bit
This bit enables or disables counting.
When this bit is set to "1", the counter is placed in trigger standby mode.
Counting starts when the software trigger bit (TRG) is set to "1" or a valid
edge (rising, falling, or both edges) of trigger input specified in the operation
mode setting bits (MOD2, MOD1, and MOD0) is input to the TIN pins.
When this bit is set to "0", counting stops.
bit0
TRG:
Software trigger bit
This bit starts the interval timer function or counter function with software.
When this bit is set to "1" while the count enable bit (CNTE) is set to "1", the
value stored in the 16-bit reload register is loaded into the 16-bit down
counter and counting starts.
When this bit is set to "0", there is no effect on operation.
The read value is "0".