Fujitsu F202RA Computer Hardware User Manual


 
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CHAPTER 12 A/D CONVERTER
Table 12.4-1 Explanation of Functions of Each Bit in the Bits in A/D Control Register 1 (ADC1)
Bit name Function
bit7 Unused bit
The value during read is not determined.
Write does not affect operations.
bit6
to
bit4
ANS2, ANS1, ANS0:
Analog input channel
selection bits
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.
bit3
ADI:
Interrupt request flag
bit
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.
bit2
ADMV:
Convertion flag bit
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.
bit1
RESV0:
Reserved bit
The value during read is not determined.
Write does not affect operations.
bit0
AD:
A/D conversion
activation bit
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.