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FUJITSU F2MC-8L F202RA User Manual

Page 190

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CHAPTER 8 8/16-BIT CAPTURE TIMER/COUNTER

Note:

When using only timer 0 of the 8/16-bit capture timer/counter in the 8-bit mode, set a value other than

111

B

in the count clock selection bits (TCS12, TCS11, TCS10) of the timer 1 control register (TCR1).

Using timer 0 with setting value TCS12, TCS11, TCS10 = 111

B

results in a malfunction.

Table 8.4-2 Explanation of Functions of Each Bit in Timer 0 Control Register (TCR0)

Bit name

Function

bit7

TIF0:
Compare match
detection flag bit

8-bit mode
When the counter value of timer 0 matches the value (comparator data latch)
set in the timer 0 data register (TDR0), this bit is set to "1".

16-bit mode
When the counter value of timer 0 matches the value set in TDR0 and the
counter value of timer 1 matches the value set in TDR1, this bit is set to "1".

An interrupt request is output when this bit and the interrupt request enable bit
(T0IEN) are "1".

bit6

TFCR0:
Compare match
detection flag clear bit

This bit is used to clear the compare match detection flag bit (TIF0). When this
bit is set to "1", the compare match detection flag is cleared. The flag is not
affected even if this bit is set to "0".

bit5

T0IEN:
Interrupt request enable
bit

This bit is used to allow and prohibit interrupt request output to the CPU.

An interrupt request is output when this bit and the interrupt request enable bit
(T0IEN) are "1".

bit4

CINV:
Count clock selection bit

This bit is used to select whether to increment the counter at the rising or
falling edge of a clock. When this bit is "0", the counter is incremented at the
falling edge of the clock. When "1", the counter is incremented at the rising
edge.

bit3

to

bit1

TCS02, TCS01, TCS00:
Clock source selection
bits

These bits are used to select the count clocks to be supplied to the counter.

Select one clock from the seven internal clocks and one external clock.

When these bits are 111

B

, the external clock is input. In this case, timer 0 can

operate as the counter function.

Note:

When external clock input is selected (TCS02, TCS01, TCS00 = 111

B

), the

P33/EC pin must be set in the input port.

bit0

TSTR0:
Timer start bit

This bit is used to start and stop the counter.

When this bit is set to "1", the counter is cleared and incremented according to
the selected count clock. When this bit is set to "0", the counter stops its
operation.

When the timer is started (TSTR0 = 0

→ 1) in the 16-bit mode, the counters of

both timer 0 and timer 1 are cleared.

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