
7751 Group User’s Manual
8–34
A-D CONVE R T E R
8.10 Repeat sweep mode 1
8.10.2 Repeat sweep mode 1 operation description
(1) When an internal trigger is selected
The A-D converter starts conversion for the input voltage from the AN
0
pin when the A-D conversion
start bit is set to “1.”
The A-D conversion of the input voltage from the AN
0
pin is completed after 49 cycles of
φ
AD
in
the 8-bit mode, or 59 cycles of
φ
AD
in the 10-bit mode. Then, the contents of the successive
approximation register (conversion result) are transferred to the A-D register 0.
The operations to all analog input pins in the group of more frequencies of use are performed.
The conversion result is transferred to the A-D register i each time each pin is converted.
The operation to one (refer to Figure 8.10.1) of analog input pins in the group of fewer frequencies
of use is performed.
The operations to all analog input pins in the group of more frequencies of use are performed again.
The operation to another one, which is different from the one selected in step
, of analog input
pins in the group of fewer frequencies of use is performed. (Refer to Figure 8.10.1.)
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 conversion for the input voltage from the AN
0
pin when the input level to
the
AD
TRG
pin changes from “H” to “L” while the A-D conversion start bit is set to “1.”
The A-D conversion of the input voltage from the AN
0
pin is completed after 49 cycles of
φ
AD
in
the 8-bit mode, or 59 cycles of
φ
AD
in the 10-bit mode. Then, the contents of the successive
approximation register (conversion result) are transferred to the A-D register 0.
The operations to all analog input pins in the group of more frequencies of use are performed.
The conversion result is transferred to the A-D register i each time each pin is converted.
The operation to one (refer to Figure 8.10.1) of analog input pins in the group of fewer frequencies
of use is performed.
The operations to all analog input pins in the group of more frequencies of use are performed again.
The operation to another one, which is different from the one selected in step
, of analog input
pins in the group of fewer frequencies of use is performed. (Refer to Figure 8.10.1.)
The operation is performed repeatedly until the A-D conversion start bit is cleared to “0” by software.
______
When the level of the
TRG
pin changes from “H” to “L” during operation, the operation at that point
is cancelled and is restarted from step
.