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CHAPTER 7 16-BIT RELOAD TIMER
7.5
Underflow operation
A transition of a counter value from 0000
H
to FFFF
H
is called "underflow". An
underflow occurs when the [set value in the reload re 1] count is reached.
■
Underflow operation
When an underflow occurs, and the RELD bit in the control register is 1, the counter loads the
value in the reload register and continues counting. If the RELD bit is 0, the counter stops at
FFFF
H
.
The UF bit of the control register is set by an underflow, and if the INTE bit is 1, an interrupt
request is generated.
Figure 7.5-1 "Underflow operation" shows underflow operation.
Figure 7.5-1 Underflow operation
Counter clock
Counter
Reloaded data
0000
H
0000
H
FFFF
H
Data load
Underflow set
Underflow set
[RELD=1]
Counter clock
Counter
[RELD=0]
-1
-1
-1
Summary of Contents for MB91150 Series
Page 1: ......
Page 2: ......
Page 3: ...FUJITSU LIMITED FR30 32 BIT MICROCONTROLLER MB91150 Series HARDWARE MANUAL ...
Page 4: ......
Page 10: ...vi ...
Page 112: ...96 CHAPTER 3 MEMORY SPACE CPU AND CONTROL UNIT ...
Page 178: ...162 CHAPTER 5 I O PORTS ...
Page 214: ...198 CHAPTER 7 16 BIT RELOAD TIMER ...
Page 240: ...224 CHAPTER 8 PPG TIMER ...
Page 310: ...294 CHAPTER 13 8 10 BIT A D CONVERTER ...
Page 318: ...302 CHAPTER 14 8 BIT D A CONVERTER ...
Page 362: ...346 CHAPTER 15 UART ...
Page 420: ...404 CHAPTER 19 PERIPHERAL STOP CONTROL ...
Page 428: ...412 CHAPTER 20 CALENDAR MACROS ...
Page 503: ...487 INDEX INDEX The index follows on the next page This is listed in alphabetic order ...
Page 510: ...494 INDEX ...
Page 512: ......