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FUJITSU F2MCTM-16LX User Manual

Page 202

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CHAPTER 11 TIMEBASE TIMER

Table 11.3-1 Functions of Timebase Timer Control Register (TBTC)

Bit name

Function

bit15

Reserved: reserved bit

Always set this bit to "1".

bit14
bit13

Undefined bits

Read: The value is undefined.
Write: No effect

bit12

TBIE:
Overflow interrupt
enable bit

This bit enables or disables an interrupt when the interval timer bit in the timebase timer
counter overflows.
When set to "0": No interrupt request is generated at an overflow (TBOF = 1).
When set to "1": An interrupt request is generated at an overflow (TBOF = 1).

bit11

TBOF:
Overflow interrupt
request flag bit

This bit indicates an overflow (carrying) in the interval timer bit in the timebase timer
counter.
When an overflow (carrying) occurs (TBOF = 1) with interrupts enabled (TBIE = 1), an
interrupt request is generated.
When set to "0": The bit is cleared.
When set to "1": Disabled. The state remains unchanged.
Read by read modify write instructions: "1" is read.
Note:
1) To clear the TBOF bit, disable interrupts (TBIE = 0) or mask interrupts using the

interrupt mask register (ILM) in the processor status.

2) The TBOF bit is cleared at a write of "0", transition to main stop mode or to PLL stop

mode, transition from subclock mode to main clock mode or to PLL clock mode,
transition from main clock mode to PLL clock mode, at a write of "0" to the timebase
timer counter clear bit (TBR), or at a reset.

bit10

TBR:
Timebase timer
counter clear bit

This bit clears all the bits in the timebase timer counter.
When set to "0" : All the bits in the timebase timer counter are cleared to "0". The

TBOF bit is also cleared.

When set to "1" : Disabled. The state remains unchanged.
Read

: "1" is always read.

bit9
bit8

TBC1, TBC0:
Interval time select
bits

These bits set the cycle of the interval timer in the timebase timer counter.

The interval time of the timebase timer is set according to the setting of the TBC1
and TBC0 bits.

One of four time intervals can be selected.