CHAPTER 12 PORT FUNCTIONS
581
User’s Manual U15195EJ5V0UD
12.5 Noise Eliminator
12.5.1 Interrupt pins
A timing controller to guarantee the noise elimination time shown below is added to the pins that operate as NMI
and valid edge inputs in port control mode. A signal input that changes in less than this elimination time is not
accepted internally.
Pin
Noise Elimination Time
P00/NMI
P01/ESO0/INTP0, P02/ESO1/INTP1
P03/ADTRG0/INTP2,
P04/ADTRG1/INTP3
P05/INTP4/TO3OFF
Analog delay (several 10 ns)
Cautions 1. The above non-maskable/maskable interrupt pins are used
to release standby mode. A clock control timing circuit is
not used since the internal system clock is stopped in
standby mode.
2. The noise eliminator is valid only in control mode.
12.5.2 Timer 10, timer 3 input pins
Noise filtering using the clock sampling shown below is added to the pins that operate as valid edge inputs to timer
10 and timer 3. A signal input that changes in less than these elimination times is not accepted internally.
Pin
Noise Elimination Time
Sampling Clock
Timer 10
P10/TIUD10/TO10
P11/TCUD10/INTP100
P12/TCLR10/INTP101
Select from f
XXTM10
f
XXTM10
/2
f
XXTM10
/4
f
XXTM10
/8
P26/TI3/INTP30/TCLR3 Select
from
f
XXTM3
/2
f
XXTM3
/4
f
XXTM3
/8
f
XXTM3
/16
Timer 3
P27/TO3/INTP31
4 to 5 clocks
Select from f
XXTM3
/32
f
XXTM3
/64
f
XXTM3
/128
f
XXTM3
/256
Cautions 1. Since the above pin noise filtering uses clock sampling, input signals are not received when
the CPU clock is stopped.
2. The noise eliminator is valid only in control mode.
Remark
f
XXTM10
: Clock of TM10 selected in PRM02 register (be sure to set PRM02 = 01H)
f
XXTM3
: Clock of TM3 selected in PRM03 register