tmp89fm42k TOSHIBA Semiconductor CORPORATION, tmp89fm42k Datasheet - Page 193

• Manufacturer Part Number: tmp89fm42k
• Description: 8 Bit Microcontroller Tlcs-870/c1 Series
• Manufacturer: TOSHIBA Semiconductor CORPORATION

RB002
13.5
13.5.1
The digital noise canceller can be used in the operation modes that use the TCA0 pin.
Noise Canceller
TA0CR<TA0NC>. When the same level is detected three times consecutively, the level of the input to the timer
is changed.
the TA0CR<TA0S> value.
sampling interval after TA0CR<TA0NC> is set has elapsed. This stabilizes the input signal.
writing is ignored.
operation. Setting TA0CR<TA0NC> to "00" disables the noise canceller. Setting TA0CR<TA0NC> to "01" or
"10" disables the TCA0 pin input.
When the digital noise canceller is used, the input level is sampled at the sampling intervals set at
Setting TA0CR<TA0NC> to any values than "00" allows the noise canceller to start operation, regardless of
When the noise canceller is used, allow the timer to start after a period of time that is equal to four times the
Set TA0CR<TA0NC> while the timer is stopped (TA0CR<TA0S> = "0"). When TA0CR<TA0S> is "1",
In the SLOW 1/2 or SLEEP 1 mode, setting TA0CR<TA0NC> to "11" selects fs/2 as the source clock for the
Setting
Table 13-4 Noise Cancel Time ( fcgck = 4 [MHz] )
TA0NC
00
01
10
11
Sampling interval
64 μs (256/fcgck)
500 ns (2/fcgck)
1 μs (4/fcgck)
None
Page 175
Time removed as noise
192 μs or less
1.5 μs or less
3 μs or less
-
Time regarded as signal
256 μs or more
2 μs or more
4 μs or more
-
TMP89FM42K