11
11-33
Ver.0.10
11.2.5 A-D Successive Approximation Register
■
A-D0 Successive Approximation Register (AD0SAR)
<Address: H'0080 0088>
Note: This register must always be accessed in halfwords.
The A-D0 Successive Approximation Register (AD0SAR), when in A-D conversion mode, is used
to read out the conversion result of the A-Dn converter, and when in comparator mode, it is used to
write a comparison value.
In A-D conversion mode, the successive approximation method is used to perform A-D conversion.
With this method, the reference voltage VREF and analog input voltages are sequentially
compared bitwise beginning with the high-order side, and the comparison result is set in the A-D0
Successive Approximation Register (AD0SAR) bits (D6-D15). After the A-D conversion is
completed, the value of this register is transferred to the 10-bit A-D0 Data Register (AD0DTn)
corresponding to the converted channel. When you read this register in the middle of A-D
conversion, you see the result in the middle of conversion.
In comparator mode, write a comparison value (the value to be compared in comparate operation)
to this register. Simultaneously with a write to this register, comparate operation with the analog
input pin that has been set by Single Mode Register 1 starts. After comparate operation, the result
is stored in the A-D0 Comparate Data Register (AD0CMP).
Use the calculation formula shown below to find the comparison value to be written to the A-D0
Successive Approximation Register (AD0SAR) during comparator mode.
<When reset:Indeterminate>
D
Bit Name
Function
R
W
0-5
No functions assigned
0
–
6-15
AD0SAR
• A-D successive approximation value
(A-D0 successive approximation
(A-D conversion mode)
value/comparison value)
• Comparison value (comparator mode)
Comparate comparison voltage [V]
VREF0 input voltage [V]
Comparison value = H'3FF
×
D0
1
2
3
4
5
6
7
8
9
10
11
12
13
14
D15
AD0SAR
A-D CONVERTERS
11.2 A-D Converter Related Registers
Summary of Contents for M32170F3VFP
Page 42: ...1 1 24 Ver 0 10 OVERVIEW 1 4 Pin Layout This is a blank page ...
Page 56: ...2 2 14 Ver 0 10 This is a blank page ...
Page 88: ...3 3 32 Ver 0 10 ADDRESS SPACE 3 7 Notes on Address Space This is a blank page ...
Page 270: ...9 9 40 Ver 0 10 DMAC 9 4 Precautions about the DMAC This is a blank page ...
Page 614: ...12 12 64 Ver 0 10 This is a blank page SERIAL I O 12 9 Precautions on Using UART Mode ...
Page 756: ...17 17 10 Ver 0 10 RAM BACKUP MODE 17 4 Exiting RAM Backup Mode Wakeup This is a blank page ...
Page 762: ...18 18 6 Ver 0 10 OSCILLATION CIRCUIT 18 2 Clock Generator Circuit This is a blank page ...
Page 831: ...CHAPTER 22 CHAPTER 22 TYPICAL CHARACTERISTICS 22 1 A D Conversion Characteristics ...
Page 833: ...Appendix 1 1 Dimensional Outline Drawing APPENDIX 1 APPENDIX 1 MECHANICAL SPECIFICATIONS ...
Page 841: ...Appendix 3 1 Precautions about Noise APPENDIX 3 APPENDIX 3 PRECAUTIONS ABOUT NOISE ...