Principles of Operation
21
2
2
2
2
2
2
2
2
2
Data Format
The KUSB-3100 module uses twos complement encoding for analog
output values. In software, you need to supply a code that
corresponds to the analog output value to output.
To convert a voltage into a twos complement code, use the following
formulas:
LSB = FSR = 20 V = 0.0048828 V
2
N
4096
Code
Offset Binary
= Vout
–
Offset
LSB
Code
Twos Complement
= Code
Offset Binary
XOR (2
N-1
)
where,
•
FSR
is the full-scale range (20 V).
•
N
is the input resolution (12 bits).
•
LSB
is the least significant bit (0.0048828).
•
Vout
is the analog voltage.
•
Offset
is the actual minus full-scale value (
–
10.0 V).
•
Code
OffsetBinary
is the raw count used by the software to represent
the voltage in offset binary notation.
•
Code
Twos Complement
is the raw count used by the software to
represent the voltage in twos complement notation.
Code
Offset Binary
= Vout – Offset
LSB
Code
OffsetBinary
=
+
5 V – (–10 V) = 3072
0.0048828 V
Summary of Contents for KUSB-3100
Page 10: ...Contents x...
Page 14: ...About this Manual xiv...
Page 15: ...1 1 Overview Features 2 Supported Software 3...
Page 18: ...Chapter 1 4...
Page 46: ...Chapter 2 32...
Page 47: ...33 3 Supported Device Driver Capabilities...
Page 86: ...Chapter 4 72...
Page 87: ...73 5 Troubleshooting General Checklist 74 Service and Support 77...
Page 100: ...Chapter 6 86...
Page 101: ...87 A Specifications...
Page 112: ...Appendix A 98...
Page 113: ...99 B Connector Pin Assignments...
Page 115: ...101 C Reading from or Writing to the Digital Registers...