Chapter 5 Operation Theory; A/D Conversion; A/D Conversion Procedure - ADLINK Technology cPCI-9116 User Manual

5
Operation Theory
The operation theory of the functions on the 9116 series is described in this
chapter. The functions include the A/D conversion, Digital I/O and General
Purpose Counter / Timer. The operation theory can help you better understand
how to configure and program the 9116 series card.
5.1

A/D Conversion

5.1.1

A/D Conversion Procedure

When using an A/D converter, users should beware of the properties of the
signal to be measured. Users can decide which channel to use and where to
connect the signals to the card. Please refer to 3.2 for signal connections. In
addition, users should define and control the A/D signal configurations,
including channels, gains, and A/D signal types.
The A/D acquisition is initiated by a trigger source; users must decide how to
trigger the A/D conversion. The data acquisition will start when a trigger
condition is met.
After the end of the A/D conversion, the A/D data is buffered in a Data FIFO.
The A/D data is then transferred into PC's memory for further processing.
There are two acquisition modes: Software Polling and Scan acquisition. They
will be described separately in the following section, including the timing, signal
source control, trigger mode, and transfer method.
34 • Operation Theory