APPLICATIONS
18.1 Application example of A-D converter
Setting of pins AN
0
to AN
7
to single sweep mode
A-D control register 0
Setting of A-D conversion start bit to “0.”
b7
b0
b7
b0
A-D control register 0
(Address 1E16
0
0
0
1
0
➀
➀
➀
)
(Address 1E16
)
A-D conversion halts.
Single sweep mode
A-D conversion start bit
0 : A-D conversion halts.
A-D conversion frequency (
See Table 12.2.1.
φAD) select bit 0
Selection of comparator function
b7
0
b0
0
Comparator function select register 0
(Address DC16
0
0 0 0 0 0
)
b7
b0
1
A-D control register 1
(Address 1F16
0
0
1
0
1
AN
AN
AN
AN
AN
AN
AN
AN
0
1
2
3
4
5
6
7
)
A-D sweep pin select bits
b1 b0
0 : Comparator function is not selected.
1
1 : AN
Resolution select bit
1 : 10-bit resolution mode
0 to AN7 (8 pins)
A-D conversion frequency (
See Table 12.2.1.
φAD) select bit 1
b7
b0
V
REF connection select bit
Comparator function select register 1
0
0 0 0 0 0 0 0
0 : Pin VREF is connected.
(Address DD16
)
b7
0
b0
AN
AN
AN10
AN11
8
9
A-D control register 2
(Address DB16
0
0
0
0
➀
➀
➀
)
0 : Comparator function is not selected.
Analog input pin select bits 1
b3 b2 b1 b0
0 ➀➀➀➀➀: Pins AN0 to AN7 are selected.
➀: It may be either “0” or “1.”
Port P7 direction register, Port P8 direction register
Interrupt disabled, no interrupt requested
b7
0
b0
0
Port P7 direction register
b7
b0
0
0 0 0 0 0
(Address 1116
)
A-D conversion interrupt control register
(Address 7016
0
0 0
0
)
AN
0
1
2
3
4
5
6
7
Interrupt disabled
AN
AN
AN
AN
AN
AN
AN
Clear the bits, corresponding to the
selected analog input pins, to “0.”
No interrupt requested
Setting of A-D conversion start bit to “1.”
b7
b0
A-D control register 0
(Address 1E16
b7
b0
0
1
)
Port P8 direction register
0
0 0
(Address 1416
)
A-D conversion starts.
AN
AN
AN10
AN11
8
9
Clear the bits, corresponding to the
selected analog input pins, to “0.”
Trigger generated, A-D conversion started
0: During A-D
conversion.
A-D conversion
interrupt request
bit = “1” ?
1: A-D conversion, using single sweep mode
with pins AN to AN , is completed.
0
7
Continued on Figure 18.1.2.
Fig. 18.1.1 Application example of A-D converter, using single sweep mode with pins AN
0
to AN11 (1)
7905 Group User’s Manual Rev.1.0
18-3
RENESAS [ RENESAS TECHNOLOGY CORP ]
