8/16-Bit Capture Timer/Counter Of Interrupts - Fujitsu F2MC-8L F202RA Hardware Manual

8.5

8/16-bit Capture Timer/Counter of Interrupts

The 8/16-bit capture timer/counter generates an interrupt if the values set in a data
register match those set in the counter when the interval timer or counter is operating.
The interrupt level is IRQ3 when generated by the 8/16-bit capture timer/counter. When
the capture is in operation and a capture edge is detected, IRQ4 is generated.
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8/16-bit Capture Timer/Counter of Interrupts
Table 8.5-1 shows the interrupt request flag bit, interrupt flag clear bit, interrupt request enable bit, and the
cause of the 8/16-bit capture timer/counter interruption.
Table 8.5-1 Interrupt Control Bits and the Cause of the 8/16-bit Capture Timer/Counter Interrupt
Interrupt request flag bit
Interrupt flag clear bit
Interrupt request enable bit
Interrupt cause
In the 8-bit mode, timer 0 and timer 1 independently generats the interrupt request for 8/16-bit capture
timer/counter. In the 16-bit mode, timer 0 generates the interrupt request. All basic operations are the same.
Timer 0 interrupt operation in the 8-bit mode is explained here.
● Timer 0 interrupt operation in the 8-bit mode
The counter value is incremented according to the selected count clock, starting at 00
value matches the value set in the comparator data latch (timer 0 data register (TDR0)) corresponding to the
timer 0 data register (TDR0), the compare match detection flag bit (TCR0: TIF0) is set to "1".
In this case, when the interrupt request flag bit is allowed (when TCR0: T0IEN = 1), timer 0 generates an
interrupt request (IRQ3) to the CPU. Set the TFCR0 bit to "1" and clear the interrupt request with the
interrupt processing routine.
When the counter value matches the value set in the comparator data latch, the TIF0 bit is set to "1"
regardless of the TFCR0 bit value.
In the 8-bit mode, timer 0 and timer 1 operate independently, and because they generate the same interrupt
request (IRQ3), determination of the interrupt request flag by software may be required.
8-bit mode
Timer 0
TCR0 : TIF0 TCR1 : TIF1
TCR0 : TFCR0 TCR1 : TFCR1
TCR0 : T0IEN TCR1 : T1IEN
The values in The values in
TDR0 match TDR1 match
those in the 8-bit those in the 8-bit
counter. counter.
CHAPTER 8 8/16-BIT CAPTURE TIMER/COUNTER
16-bit mode
Timer 1 Timer 0 + timer 1
TCR0 : TIF0
TCR0 : TFCR0
TCR0 : T0IEN
The values in
TDR0 and TDR1
match those in the
16-bit counter.
Capture mode
Timer 0 or timer 0 +
timer 1
TCCR : CPIF
TCCR : CFCLR
TCCR : CPIEN
A capture edge is
detected.
. When the counter
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