Table of Contents
Advertisement
Table 9.3-1 Functions of bits in timebase timer control register (TBTC)
Bit name
RESV:
bit15
Reserved bit
bit14
Undefined bits
bit13
TBIE:
bit12
Interrupt request
permit bit
TBOF:
bit11
Interrupt request flag
bit
TBR:
bit10
Timebase timer
initializing bit
TBC1, TBC0:
bit9
Interval time selection
bit8
bit
Always write "1" to this bit.
•
Undefined value in reading
•
No effect on write operation
This bit permits or prohibits output of interrupt requests to the CPU.
•
An interrupt request is output if this bit and the interrupt request flag bit
(TBOF) are set to "1".
This bit is set to "1" when the bit specified by the timebase timer counter
overflows.
•
An interrupt request is output if this bit and the interrupt request permit
bit (TBIF) are set to "1".
•
This bit is cleared by writing "0" but is not changed by writing "1" so
that this operation does not affect other functions.
Notes:
•
Clearing of the interrupt request flag bit (TBOF) must be implemented
in the state where the timebase timer interrupt is prohibited by the
interrupt request permit bit (TBIE) or by the interrupt level mask
register (ILM) setting of the processor status (PS).
•
This bit is cleared to "0" by writing "0", a transition to the main stop
mode, a transition to the PLL stop mode, a transition from the sub-
clock mode to the main clock mode, a transition from the sub-clock
mode to the PLL clock mode, a transition from the main clock mode to
the PLL clock mode, writing "0" to the timebase timer initializing bit
(TBR) or a reset.
This bit clears the timebase timer counter.
•
When "0" is written to this bit, the counter is cleared and the TBOF bit
is cleared. This bit is not changed by writing "1" so that this operation
does not affect other functions.
[Reference]
The readout value is always "1".
This bit specifies the cycle of the interval timer.
•
The bit for the interval timer in the timebase timer counter is specified.
•
The interval time can be selected out of four types.
CHAPTER 9 TIMEBASE TIMER
Function
191
Advertisement
Table of Contents
