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CHAPTER 23 10-BIT A/D CONVERTER
23.7
Notes on Use of 10-bit A/D Converter
This section summarizes notes on using the 10-bit A/D converter.
■
Notes on Use of 10-bit A/D Converter
●
Notes on programmed setup
•
When the A/D conversion function is used, the contents of the ADDH and ADDL registers are retained
upon completion of A/D conversion. During A/D conversion, the values resulting from the last
conversion are loaded.
•
Do not re-select the analog input channel (ADC1: ANS3 to ANS0) while the AD conversion function is
running, in particular, during continuous activation. Disable continuous activation (ADC2: EXT = 0)
before re-selecting the analog input channel.
•
Starting the reset, stop, or watch mode stops the 10-bit A/D converter and initializes each register.
•
The CPU cannot return from interrupt processing if the interrupt request flag bit (ADC1: ADI) is 1 with
interrupt requests enabled (ADC2: ADIE = 1). Be sure to clear the ADI bit within the interrupt service
routine.
●
Note on interrupt requests
If A/D conversion is reactivated (ADC1: AD = 1) and terminated at the same time, the interrupt request
flag bit (ADC1: ADI) is set.
●
Error
As |V
CC
-V
SS
| decreases, an error increases relatively.
●
10-bit A/D converter and analog input power-on/shut-down sequences
Turn on the 10-bit A/D converter power supply (V
CC
), and analog input (AN00 to AN07) at the same as or
after turning on the digital power supply (DV
CC,
).
In addition, turn off the digital power supply (DV
CC
) either at the same time as or after turning off the 10-
bit A/D converter analog input (AN00 to AN07).
Be careful not to let the analog input exceed the voltage of the digital power supply when turning the 10-bit
A/D converter on and off.
●
Conversion time
The conversion speed of the A/D conversion function is affected by the clock mode, main-clock oscillation
frequency, and main-clock speed switching (gear function).
Example: Sampling time = CKIN
×
(ADC2: TIM1/0 setting)
Compare time = CKIN x 10 (fixed value) + MCLK
Conversion time = A/D start processing time + sampling time + compare time
•
The error max. 1CKIN-1MCLK may occur depending on the timing of A/D startup.
•
Program the software satisfied with "sampling time" and "compare time" in A/D conversion of data
sheet.
Summary of Contents for F2 MC-8FX Family
Page 2: ......
Page 4: ......
Page 34: ...20 CHAPTER 1 DESCRIPTION ...
Page 38: ...24 CHAPTER 2 HANDLING DEVICES ...
Page 39: ...25 CHAPTER 3 MEMORY SPACE This chapter describes memory space 3 1 Memory Space 3 2 Memory Map ...
Page 56: ...42 CHAPTER 5 CPU ...
Page 73: ...59 CHAPTER 6 CLOCK CONTROLLER ...
Page 96: ...82 CHAPTER 6 CLOCK CONTROLLER ...
Page 104: ...90 CHAPTER 7 RESET ...
Page 105: ...91 CHAPTER 8 INTERRUPTS This chapter explains the interrupts 8 1 Interrupts ...
Page 174: ...160 CHAPTER 10 TIMEBASE TIMER ...
Page 184: ...170 CHAPTER 10 TIMEBASE TIMER ...
Page 218: ...204 CHAPTER 13 WATCH PRESCALER ...
Page 257: ...243 CHAPTER 16 8 16 BIT COMPOSITE TIMER ...
Page 261: ...247 CHAPTER 16 8 16 BIT COMPOSITE TIMER ...
Page 288: ...274 CHAPTER 16 8 16 BIT COMPOSITE TIMER ...
Page 301: ...287 CHAPTER 17 16 BIT PPG TIMER ...
Page 316: ...302 CHAPTER 17 16 BIT PPG TIMER ...
Page 382: ...368 CHAPTER 21 UART SIO DEDICATED BAUD RATE GENERATOR ...
Page 390: ...376 CHAPTER 22 I2C ...
Page 395: ...381 CHAPTER 22 I2C ...
Page 399: ...385 CHAPTER 22 I2C ...
Page 430: ...416 CHAPTER 23 10 BIT A D CONVERTER ...
Page 476: ...462 CHAPTER 24 LCD CONTROLLER ...
Page 482: ...468 CHAPTER 25 LOW VOLTAGE DETECTION RESET CIRCUIT ...
Page 494: ...480 CHAPTER 26 CLOCK SUPERVISOR ...
Page 507: ...493 CHAPTER 27 REAL TIME CLOCK ...
Page 523: ...509 CHAPTER 27 REAL TIME CLOCK ...
Page 532: ...518 CHAPTER 27 REAL TIME CLOCK ...
Page 536: ...522 CHAPTER 28 256 KBIT FLASH MEMORY ...
Page 554: ...540 CHAPTER 28 256 KBIT FLASH MEMORY ...
Page 564: ...550 CHAPTER 29 EXAMPLE OF SERIAL PROGRAMMING CONNECTION ...
Page 595: ...581 INDEX INDEX The index follows on the next page This is listed in alphabetic order ...
Page 596: ...582 INDEX Index ...
Page 597: ...583 INDEX ...
Page 600: ...586 Pin Function Index ...
Page 602: ......