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134
μ
PD75236
Table 5-2 Interrupt Request Flag Set Signals
(2)
Noise eliminator and edge detection mode register
INT0, INT1 and INT2 each have the configuration shown in Figs. 5-2 and 5-3 and serve as the external
interrupt input capable of selecting detected edges.
INT0 has a function of eliminating noise with sampling clock. Pulses having a shorter width than 2
sampling clock cycles
*
are eliminated as noise by noise eliminator.
However, pulses having a larger width than 1 sampling clock cycle may be acknowledged as an inter-
rupt signal depending on the sampling timing. Pulses having a larger width than 2 sampling clock cycles
are securely acknowledged as an interrupt signal.
INT0 has two sampling clocks,
Φ
and f
x
/64 and can select and use either clock. Selection is made by bit
3 (IM03) of the edge detection mode register (refer to
Fig. 5-4
).
IRQ2 is set by detecting the rising edge of INT2 pin input.
Edge detection mode registers (IM0 and IM1) to select detection edge have the format shown in Fig. 5-4.
IM0 and IM1 each are set by a 4-bit memory manipulation instruction. RESET input clears all bits to 0
and specifies INT0, INT1 and INT2 for the rising edge.
*
When sampling clock is
Φ
When sampling clock is fx/64 : 128/f
X
: 2t
CY
Note
1. Since INT0 samples by clock, it is not operated in the standby mode.
2. Pulses are input to the INT0/P10 pin serving as a port via the noise eliminator. Thus, input pulses
having two sampling clock cycles or larger.
Interrupt Request Flag Set Signal
Set by the reference time interval signal generated by the basic interval timer.
Set upon detection of the rising or falling edge of the INT4/PO0 input signal.
Set upon detection of the INT0/P10 pin input signal edge. The detected edge is selected
using the INT0 mode register (IM0).
Set upon detection of the INT1/P11 pin input signal edge. The detected edge is selected
using the INT1 mode register (IM1).
Set by the serial data transfer operation end signal of the serial interface.
Set by the match signal from the timer/event counter #0.
Set by the match signal from the timer/pulse generator.
Set by the key scan timing signal from the display controller.
Set by a signal from the watch timer.
Set upon detection of the rising edge of the INT2/P12 pin input signal.
Interrupt
Request Flag
IRQBT
IRQ4
IRQ0
IRQ1
IRQCSI0
IRQT0
IRQTPG
IRQKS
IRQW
IRQ2
Interrupt
Enable Flag
IEBT
IE4
IE0
IE1
IECSI0
IET0
IETPG
IEKS
IEW
IE2
#