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CHAPTER 12 16-BIT INPUT/OUTPUT TIMER
12.5.1 Operation of free-running timer
This section explains the operation and timing of the free-running timer.
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Operation of free-running timer
The free-running timer starts counting at a counter value of "0000" after clearing reset operation.
This counter value is used as a reference time for output compare and input capture.
The count value is cleared under the following conditions:
•
Overflow occurs
•
Compare match is found with the output compare value 0 (mode setting is required)
•
SCLR bit of TCCS register is set to "1"
•
TCDT register is set to "0000"
•
Reset occurs
An interrupt occurs if an overflow is generated or the counter value of free-running timer the
value of compare register 0 matches compare results (a compare results match interrupt
requires mode setting).
Figure 12.5-1 shows the timing chart of the counter cleared because of an overflow. Figure
12.5-2 shows the timing chart of the counter cleared because of a compare results match.
Figure 12.5-1 Timing chart of counter cleared because of overflow
Counter value
Reset
Interrupt
FFFF
H
BFFF
H
7FFF
H
3FFF
H
0000
H
Time
Summary of Contents for MB90480 Series
Page 2: ......
Page 4: ......
Page 10: ...vi ...
Page 128: ...106 CHAPTER 4 RESET ...
Page 174: ...152 CHAPTER 6 LOW POWER CONSUMPTION MODE ...
Page 198: ...176 CHAPTER 7 MODE SETTING ...
Page 220: ...198 CHAPTER 9 TIMEBASE TIMER ...
Page 238: ...216 CHAPTER 11 WATCH TIMER ...
Page 280: ...258 CHAPTER 12 16 BIT INPUT OUTPUT TIMER ...
Page 406: ...384 CHAPTER 17 8 10 BIT A D CONVERTER ...
Page 478: ...456 CHAPTER 20 CHIP SELECTION FACILITY ...
Page 494: ...472 CHAPTER 21 ADDRESS MATCH DETECTION FUNCTION ...
Page 498: ...476 CHAPTER 22 ROM MIRROR FUNCTION SELECTION MODULE ...
Page 526: ...504 CHAPTER 23 2M 3M BIT FLASH MEMORY ...
Page 536: ...514 CHAPTER 24 EXAMPLES OF MB90F481B MB90F482B MB90F488B MB90F489B SERIAL PROGRAMMING ...
Page 570: ...548 CHAPTER 25 PWC TIMER ONLY MB90485 SERIES ...
Page 688: ......