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CHAPTER 16 8/10-BIT A/D CONVERTER
16.1 Overview of the 8/10-Bit A/D Converter
The 8/10-bit A/D converter has a function for converting the analog input voltage into a
10-bit or 8-bit value using the RC-type successive approximation conversion method.
s Functions of the 8/10-Bit A/D Converter
The following shows the functions of the 8/10-bit A/D converter:
The minimum conversion time is 6.13
s (for a machine clock of 16 MHz; includes the
sampling time).
The minimum sampling time is 2.0
s (for a machine clock of 16 MHz).
The converter uses the RC-type successive approximation conversion method with a sample
hold circuit.
A resolution of 10 bits or 8 bits can be selected.
The input signal can be set using a program from the 8-channel analog input pins.
At the end of A/D conversion, an interrupt request can be generated and EI2OS can be
activated.
If A/D conversion is performed while an interrupt is enabled, the conversion data protection
function is activated.
The conversion can be activated by software, 16-bit reload timer 1 output (rising edge), and
16-bit free-running timer zero detection edge.
Table 16.1-1 "8/10-bit A/D Converter Conversion Modes" lists four types of conversion modes.
Table 16.1-1 8/10-bit A/D Converter Conversion Modes
Conversion mode
Single conversion
Scan conversion
Single conversion mode 1
Single conversion mode 2
Converts the input of a specified
channel (single channel) just once.
Converts the inputs of two or more
consecutive channels (up to eight
channels) just once.
Continuous conversion mode
Converts the input of a specified
channel (single channel) repeatedly.
Converts the inputs of two or more
consecutive channels (up to eight
channels) repeatedly.
Stop conversion mode
Converts the input of a specified
channel (single channel), after which
it is on standby for the next
activation.
Converts the inputs of two or more
consecutive channels (up to eight
channels) just once, after which it is
on standby for the next activation.