User guide

August 2001 147
Working with MVIP-90 Data Streams
Numbering MVIP Streams
Of the 16 data streams, the first eight are input and the second
eight are output. Together, the first input (0) and first output (8)
streams form the bidirectional stream 0, as shown in Figure 25.
The second input (1) and second output (9) form the
bidirectional stream 1, and so on through the eighth input (7)
and eighth output (15), which form the bidirectional stream 7.
Although the driver uses 16 streams, the application only sees
the eight bidirectional streams.
Input and output streams are designated as DSix and DSox
where DS stands for data stream; i stands for in; o stands for
out; and x stands for the number of the bidirectional stream, 0
through 7. For example, an application would refer to the input
and output streams that make up the seventh bidirectional
stream as DSi6 and DSo6. The driver interprets these stream
assignments as streams 6 and 14, as shown in Figure 25.
Figure 25. Data Stream Numbering
The terms ‘input’ and ‘output’ are used in reference to the
resource board. A DSix stream carries data from the network to
the resource board (input to the resource) while DSox streams
carry data from the resource to the network (output from the
resource). Network boards transmit data on input streams and
receive data on output streams.
0
8
1
9
2
10
3
11
4
12
5
13
6
14
7
15
DSi0
DSo0
Input
Output
Input
Output
Input
Output
Input
Output
Input
Output
Input
Output
Input
Output
Input
Output
DSi1
DSo1
DSi2
DSo2
DSi3
DSo3
DSi4
DSo4
DSi5
DSo5
DSi6
DSo6
DSi7
DSo7
Stream 0
Stream 1
Stream 2
Stream 3
Stream 4
Stream 5
Stream 6
Stream 7