Table of Contents
Advertisement
A-D control register 0
b7
b6
b5
b4
b3
b2
b1
b0
A-D control register 0 (Address 1E
Bit
Analog input select bits
0
(Valid in one-shot and repeat
modes) (Note 1)
1
2
A-D operation mode select bit 0
3
4
Trigger select bit
5
6
A-D conversion start bit
A-D conversion frequency
7
(
) select bit 0
AD
Notes 1: These bits are ignored in the single sweep, repeat sweep mode 0, and repeat sweep
mode 1. (They may be either "0" or "1.")
2: When selecting an external trigger, the AN
pin.
3: Use the A-D operation mode select bit 1 (bit 2 at address 1F
repeat sweep mode 0 or repeat sweep mode 1.
4: Writing to each bit (except bit 6) of the A-D control register 0 must be performed while
the A-D converter halts.
7751 Group User's Manual
)
16
Bit name
b2 b1 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
b4 b3
0 0 : One-shot mode
0 1 : Repeat mode
1 0 : Single sweep mode
1 1 : Repeat sweep mode 0 /
Repeat sweep mode 1 (Note 3)
0 : Internal trigger
1 : External trigger
0 : Stop A-D conversion
1 : Start A-D conversion
When A-D conversion frequency
(
) select bit 1 (bit 4 at address
AD
1F
) = "0,"
16
0 : f
divided by 4, or f
2
1 : f
divided by 2, or f
2
When A-D conversion frequency
(
) select bit 1 (bit 4 at address
AD
1F
) = "1,"
16
0 : f
or f
2
1 : Not selected
APPENDIX
Appendix 3. Control registers
Functions
selected
0
selected
1
selected
2
selected
3
selected
4
selected
5
selected
6
selected (Note 2)
7
divided by 4
4
divided by 2
4
4
pin cannot be used as an analog input
7
) to select either the
16
At reset
RW
RW
Undefined
RW
Undefined
RW
Undefined
0
RW
0
RW
RW
0
0
RW
0
RW
20–11
Advertisement
Table of Contents
