Table 12.4-1 Explanation of Functions of Each Bit in the Bits in A/D Control Register 1 (ADC1)
Bit name
bit7
Unused bit
bit6
ANS2, ANS1, ANS0:
to
Analog input channel
bit4
selection bits
ADI:
bit3
Interrupt request flag
bit
ADMV:
bit2
Convertion flag bit
RESV0:
bit1
Reserved bit
AD:
bit0
A/D conversion
activation bit
•
The value during read is not determined.
•
Write does not affect operations.
This bit is used to select which pin to be used as an analog input from AN0 to
AN7.
When software is activated (ADC2: EXT = 0), this bit can be rewritten
concurrently with the activation of A/D conversion (AD = 1).
Note:
Pins not used as analog inputs can be used as general-purpose ports.
•
When A/D conversion functions are enabled:
•
When A/D conversion is completed, "1" is set to this bit.
•
When this bit and the bit for enabling an interrupt request (ADC2: ADIE) are
"1", an interrupt request is output.
•
At write, this bit is cleared with "0". When "1" is set to this bit, nothing is
changed or affected by this.
This bit indicates that A/D conversion is being performed, when A/D conversion
functions are enabled.
During conversion (comparison), this bit is set to "1".
Note:
This bit is read-only. The written value is ignored and nothing is affected by
the value.
•
The value during read is not determined.
•
Write does not affect operations.
•
This bit is used to activate A/D conversion functions with software.
•
In the state where continuous activation is not performed (ADC2: EXT = 0),
when "1" is set to this bit, A/D conversion functions are activated.
Notes:
• Even if "0" is written to this bit, the operation of A/D conversion functions
cannot be stopped. The read value is always "0".
• During continuous activation, this bit is ignored.
CHAPTER 12 A/D CONVERTER
Function
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