Fujitsu F2MC-16LX Hardware Manual page 457

Table 19.3-4 Functional Explanation of Each Bit in the A/D Data Register (ADCR0/ADCR1)
Bit name
bit15 S10:
A/D
conversion
resolution
selection bit
bit14 ST1,ST0:
bit13 Sampling
time setting
bit
bit12 CT1,CT0:
bit11 Comparison
time setting
bit
bit10 Undefined
bit
bit9 D9 to D0
to
bit0
Notes:
• Rewrite the S10 bit always when the A/D operation before the conversion is stopped. When
updating after the conversion, the ADCR contents become undefined.
• Always use the word transfer instruction (MOVWA, 0042H, etc.) to read the ADCR register by
specifying the 10 bit mode.
• This bit is used to select the A/D conversion resolution.
• When "0" and "1" are written in the S10 bit, 10-bit and 8-bit resolutions are selected,
respectively.
Note:
The A/D data bits used are different depends on the resolution.
• This bit is used to select the sampling time at the A/D conversion.
• When the A/D is started, the set time and the analog input are fetched into the ST1 and ST0
bits.
Note:
When the setting for "00" 6 MHz is provided during the 24 MHz operation, the normal
analog voltage sometime cannot be fetched.
• This bit is used to select the comparison time at the A/D conversion.
• The analog input is fetched (sampling time elapsed), the CT1 and CT0 bits are set, the
conversion result data is determined, and then they are stored in the bit 9 to bit 0 of this register.
Note:
When the setting for "00" 6 MHz is provided during the 24 MHz operation, the normal
analog conversion value sometime cannot be fetched.
The read value is irregular. Nothing is affected when it is written.
• The A/D conversion result is stored and the register is updated at every conversion termination.
• The final conversion value is stored usually.
• The initial value of the ADCR register is irregular.
Note:
The conversion data protection function is provided. (Please refer to "19.4 Explanation of
Operation of 8/10-bit A/D Converter".)
Do not write data in the D9 to D0 bits during the A/D conversion.
CHAPTER 19 8/10-BIT A/D CONVERTER
Functions
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