
7702/7703 Group User’s Manual
8–22
A-D CONVERTER
8.7.2 Single sweep mode operation description
(1)
When an internal trigger is selected
 The operation for the input voltage from the AN0 pin starts when the A-D conversion start bit is
set to “1.”
 The A-D conversion of the input voltage from the AN0 pin is completed after 57 cycles of
φAD. Then,
the contents of the successive approximation register (conversion result) are transferred to the
A-D register 0.
 The operation to all selected analog input pins is performed.
The conversion result is transferred to the A-D register i each time each pin is converted.
 When the step  is completed, the A-D conversion interrupt request bit is set to “1.”
 The A-D conversion start bit is cleared to “0” and the A-D converter stops operation.
(2)
When an external trigger is selected
 The A-D converter starts operation for the input voltage from the AN0 pin when the input level to
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the ADTRG pin changes from “H” to “L” while the A-D conversion start bit is “1.”
 The A-D conversion of the input voltage from the AN0 pin is completed after 57 cycles of
φAD. Then,
the contents of the successive approximation register (conversion result) are transferred to the
A-D register 0.
 The operation to all selected analog input pins is performed.
The conversion result is transferred to the A-D register i each time each pin is converted.
 When the step  is completed, the A-D conversion interrupt request bit is set to “1.”
 The A-D conversion stops operation.
The A-D conversion start bit remains set to “1” after the operation is completed. Accordingly, the
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operation of the A-D converter can be performed again from step  when the level of the ADTRG pin
changes from “H” to “L.”
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When the level of the ADTRG pin changes from “H” to “L” during operation, the operation at that point
is cancelled and is restarted from step .
Figure 8.7.2 shows the conversion operation in the single sweep mode.
8.7 Single sweep mode