A-D CONVERTER
12.8 Repeat mode
12.8 Repeat mode
In the repeat mode, the A-D conversion for an input voltage from one selected analog input pin is performed
repeatedly.
In this mode, no A-D conversion interrupt request occurs. Additionally, the A-D conversion start bit (bit 6 at
address 1E16) remains set to “1” until it is cleared to “0” by software, and the A-D converter repeats its
operation while the A-D conversion start bit = “1.”
This mode can be used with analog input pin AN (i = 0 to 11).
i
12.8.1 Settings for repeat mode
Figures 12.8.1 and 12.8.2 show initial setting examples for related registers in the repeat mode.
A-D control registers 0, 1, and 2
b7
b0
A-D control register 0
(Address 1E16
1
0 0
0
)
Analog input pin select bits 0
b2b1 b0
0 0 0 : AN
0 0 1 : AN
0 1 0 : AN
0 1 1 : AN
1 0 0 : AN
1 0 1 : AN
1 1 0 : AN
1 1 1 : AN
0
1
2
3
4
5
6
7
selected
selected
selected
selected
selected
selected
selected
selected
Repeat mode
A-D conversion start bit
0 : A-D conversion halts.
A-D conversion frequency (φAD) select bit 0
See Table 12.2.1.
b7
b0
A-D control register 1
0 0
0
✕ ✕
(Address 1F16
)
Resolution select bit
0 : 8-bit resolution mod
1 : 10-bit resolution mode
A-D conversion frequency (φAD) select bit 1
See Table 12.2.1.
V
REF connection select bit
0 : Pin VREF connected
b7
b0
A-D control register 2
(Address DB16
0
0
0 0
)
Analog input pin select bits 1
b3 b2 b1 b0
0
X X X : AN
0
8
9
to AN
selected
selected
7
selected
1 0 0 0 : AN
1 0 0 1 : AN
1 0 1 0 : AN10 selected
1 0 1 1 : AN11 selected
1 1 0 0 : Do not select.
1 1 1 1 : Do not select.
✕ : It may be either “0” or “1.”
Continued on Figure 12.8.2.
Fig. 12.8.1 Initial setting example for related registers in repeat mode (1)
7905 Group User’s Manual Rev.1.0
12-26
RENESAS [ RENESAS TECHNOLOGY CORP ]
