
7702/7703 Group User’s Manual
8–26
A-D CONVERTER
8.8.2 Repeat 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.
The operation to all selected analog input pins is performed again.
The operation is performed repeatedly until the A-D conversion start bit is cleared to “0” by
software.
(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
______
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.
The operation to all selected analog input pins is performed again.
The operation is performed repeatedly until the A-D conversion start bit is cleared to “0” by
software.
______
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 8.8.2 shows the conversion operation in the repeat sweep mode.
8.8 Repeat sweep mode