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CHAPTER 12 A/D CONVERTER
Figure 12.6-2 Setting A/D Conversion Functions (at Continuous Activation)
When continuous activation is enabled, A/D conversion is activated on a rising edge of the selected input
clock and the operations of A/D conversion functions are started. When continuous activation is disabled
(ADC2: EXT = 0), continuous activation is stopped and activation with software is possible.
■
Operations of A/D Conversion Functions
The operations of the A/D converter are described here. It takes about 38 instruction cycles from activating
A/D conversion to completing it.
1. When A/D conversion is activated, the conversion in-progress flag bit is set (ADC1: ADMV = 1), and
the analog input set is connected to the sample hold circuit.
2. During about 16 instruction cycles, the voltage of the analog input is captured and held in the capacitor
for internal sample hold. This voltage is held until A/D conversion has been completed.
3. The comparator compares the voltage captured and held in the capacitor for sample hold with the
reference voltage for A/D conversion from the MSB to the LSB. The results are transferred to the
ADDH and ADDL registers in turn.
4. When all the results have been transferred to the ADDH and ADDL registers, the conversion in-
progress flag bit is cleared (ADC1: ADMV = 0), and the interrupt request flag bit is set (ADC1: ADI =
1).
bit7
bit6
bit5
bit4
bit3
bit2
bit1
bit0
ADC1
ANS2
ANS1 ANS0
ADI
ADMV RESV0
AD
ADC2
RESV4 RESV3
ADCK
ADIE RESV2
EXT
RESV1
0
0
0
1
1
ADDH
ADDL
ADEN
: Used bit
: Unused bit
1
: Set "1"
0
: Set "0"
: Set "1" to an appropriate bit
The results of A/D conversion are stored.
The results of A/D conversion are stored.
Содержание F2MC-8L F202RA
Страница 2: ......
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Страница 32: ...16 CHAPTER 1 OVERVIEW ...
Страница 90: ...74 CHAPTER 3 CPU ...
Страница 142: ...126 CHAPTER 5 TIME BASE TIMER POPW A RETI ENDS END ...
Страница 150: ...134 CHAPTER 6 WATCHDOG TIMER ...
Страница 174: ...158 CHAPTER 7 8 BIT PWM TIMER User processing POPW A XCHW A T Restoring A and T POPW A RETI ENDS ...
Страница 176: ...160 CHAPTER 7 8 BIT PWM TIMER ...
Страница 220: ...204 CHAPTER 8 8 16 BIT CAPTURE TIMER COUNTER ...
Страница 240: ...224 CHAPTER 9 12 BIT PPG TIMER ...
Страница 258: ...242 CHAPTER 10 EXTERNAL INTERRUPT CIRCUIT 1 EDGE PUSHW A User processing POPW A XCHW A T POPW A RETI ENDS END ...
Страница 274: ...258 CHAPTER 11 EXTERNAL INTERRUPT CIRCUIT 2 LEVEL ...
Страница 362: ...346 CHAPTER 15 BUZZER OUTPUT ...
Страница 371: ...355 CHAPTER 16 WILD REGISTER FUNCTION 16 3 5 Data Test Set Register WROR A test register Do not access this register ...
Страница 390: ...374 CHAPTER 17 FLASH MEMORY ...
Страница 419: ...403 INDEX INDEX The index follows on the next page This is listed in alphabetic order ...
Страница 434: ...418 INDEX ...
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