Fujitsu F2MC-8FX Hardware Manual page 433

Table 23.4-1 Functions of Bits in A/D Control Register 1 (ADC1)
Bit name
bit7 ANS3, ANS2,
bit6 ANS1, ANS0:
bit5 Analog input channel
bit4 select bits
ADI:
bit3 Interrupt request flag
bit
ADMV:
bit2
Conversion flag bit
ADMVX:
bit1 Analog switch control
bit
AD:
bit0 A/D conversion startup
bit
Select the analog input pin to be used from among AN00 to AN07.
Note that the number of analog input pins differs depending on the series.
• When A/D conversion is activated (AD = 1) via software (ADC2: EXT = 0), these bits can be
updated at the same time.
Note: When the ADMV bit is "1", do not update these bits.
The pins not used as analog input pins can be used as general-purpose ports.
Detects the termination of A/D conversion.
• When the A/D conversion function is used, the bit is set "1" upon termination of A/D conversion.
• Interrupt requests are output when this bit and the interrupt request enable bit (ADC2: ADIE) are
both "1".
• When written to this bit, "0" clears it; "1" leaves it unchanged with no affect on others.
• When read by a read-modify-write instruction, the bit returns "1".
Indicates that conversion is ongoing during execution of the A/D conversion function.
• The bit contains "1" during conversion.
This bit is read-only. Any value attempted to be written is meaningless and has no effect on
operation.
Controls the analog switch for shutting down the internal reference power supply.
• When the external impedance of the AVR pin is high, rush current flows immediately after A/D
startup and may affect A/D conversion precision. In this kind of situation, this can be avoided by
setting this bit to "1" before A/D startup.
Set the bit to "0" before switching to standby mode, in order to reduce current consumption.
• Note that some series do not have AVR pins, and are internally connected to AV
Starts the A/D conversion function via software.
• Writing "1" to the bit starts the A/D conversion function.
Note: Writing "0" to this bit will not stop operation of the A/D conversion function. The value
read is always "0".
A/D conversion startup by this bit is disabled with EXT="1".
A/D converter re-starts by writing "1" to this bit during A/D conversion with EXT = "0".
CHAPTER 23 10-BIT A/D CONVERTER
Function
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CC
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