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Chapter 11
16-bit Timer/Event Counter T
User’s Manual U16580EE3V1UD00
11.6.2 External event count mode
In the external event count mode, count up starts upon external event input (TEVTTn pin). (The
external event input (TEVTTn) is used as the count clock, regardless of bit TTnEEE of the TTnCTL1
register.)
In the external event count mode, the counter is cleared only upon a match between the counter and
the value of the TTnCCR0 register. Counter clearing using the TTnCCR1 register does not work.
However, the value of the TTnCCR1 register is transferred to the TTnCCR1 buffer register, compared to
the counter value, and a compare match interrupt (INTTTnCC1) is output.
The TTnCCR0 and TTnCCR1 registers can be rewritten with the anytime write method, regardless of
the value of bit TTnCE.
Pin TOTn1 toggles output controlled when bit TTnOE1 is set to 1.
When using only one compare register channel, it is recommended to set the TTnCCR1 register to
FFFFH.
[External event count operation flow]
<1> TTnCTL1 register bits TTnMD3 to TTnMD0 = 0001B (mode setting)
Edge detection set with TTnIOC2 register bits TTnEES1 and TTnEES0 (TTnEES1,
TTnEES0 = setting other than 01B)
<2> TTnCTL0 register bit TTnCE = 1 (count enable)
<3> TEVTTn pin input edge detection (count-up start)
Cautions: 1. In external event count mode, when the content of the TTnCCR0 register is set to
m, the number of TEVTTn pin input edge detection times is m+1.
2. In external event count mode, do not send the TTnCCR0 register to 0000H.
3. When the TTnCCR1 register value is set to 0000H in external event count mode
the corresponding interrupt (INTTTnCC1) does not occur immediately after start,
but after the first overflow of the timer (FFFFH to 0000H).
4. TOTn0 pin output cannot be used during external event count mode. Alternatively
use the interval timer mode (refer to chapter 11.6.1 “Interval timer mode” on
page 487) and set TTnEEE = 1 in conjunction with TOTn0 pin output.
Remark:
n = 0, 1
Summary of Contents for MuPD70F3187
Page 6: ...6 Preface User s Manual U16580EE3V1UD00 ...
Page 16: ...16 User s Manual U16580EE3V1UD00 ...
Page 28: ...28 User s Manual U16580EE3V1UD00 ...
Page 32: ...32 User s Manual U16580EE3V1UD00 ...
Page 84: ...84 Chapter 2 Pin Functions User s Manual U16580EE3V1UD00 MEMO ...
Page 144: ...144 Chapter 3 CPU Functions User s Manual U16580EE3V1UD00 MEMO ...
Page 312: ...312 Chapter 9 16 Bit Timer Event Counter P User s Manual U16580EE3V1UD00 MEMO ...
Page 534: ...534 Chapter 11 16 bit Timer Event Counter T User s Manual U16580EE3V1UD00 ...
Page 969: ...969 Chapter 20 Port Functions User s Manual U16580EE3V1UD00 MEMO ...
Page 970: ...970 Chapter 20 Port Functions User s Manual U16580EE3V1UD00 ...
Page 976: ...976 Chapter 22 Internal RAM Parity Check Function User s Manual U16580EE3V1UD00 MEMO ...
Page 984: ...984 Chapter 23 On Chip Debug Function OCD User s Manual U16580EE3V1UD00 MEMO ...
Page 1006: ...1006 Chapter 24 Flash Memory User s Manual U16580EE3V1UD00 MEMO ...
Page 1036: ...1036 Chapter 27 Recommended Soldering Conditions User s Manual U16580EE3V1UD00 MEMO ...
Page 1046: ...1046 Appendix A Index User s Manual U16580EE3V1UD00 MEMO ...
Page 1052: ...1052 User s Manual U16580EE3V1UD00 ...
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