Measurement Computing Data Translation DT3034, User Manual

Page: 74 / 178

Principles of Operation
73
Two dynamic digital output lines are provided: 0 and 1. These lines are set to a value of 0 on
power up; a reset does not affect the values of the dynamic digital output lines. Note that
these lines are provided in addition to the other 16 digital I/O lines; see
page 94 for more
information on the digital I/O features.
Using software, specify the values to write to the dynamic digital output lines using the
analog input channel list. As each entry in the analog input channel list is read, the
corresponding value you specified is output to the dynamic digital output lines.
For DT3034 boards, you can specify the following values for the dynamic digital output lines:
0 (00 in binary format), 1 (01 in binary format), 2 (10 in binary format), or 3 (11 in binary
format), where a value of 1 means that the line goes high and a value of 0 means that the line
goes low. Each bit in binary format corresponds to the value to write to the dynamic digital
output line. For example, a value of 1 (01 in binary format) means that a value of 1 is output to
dynamic digital output line 0 and value of 0 is output to dynamic output line 1. Similarly, a
value of 2 (10 in binary format) means that a value of 0 is output to dynamic digital output line
0 and value of 1 is output to dynamic output line 1.
For example, assume that the analog input channel list contains channels 5, 6, 7, 8; that
dynamic digital output operations are enabled; and that the values to write to the dynamic
digital output lines are 2, 0, 1, 3.
Figure 21 shows this configuration.
Figure 21: An Example Using Dynamic Digital Outputs
As analog input channel 5 is read, 1 is output to dynamic digital output line 1, and 0 is output
to dynamic output line 0 (since 2 in binary format is 10). As analog input channel 6 is read, 0 is
output to both dynamic digital output lines. As analog input channel 7 is read, 0 is output to
dynamic digital output line 1, and 1 is output to dynamic output line 0 (since 1 in binary
format is 01). As analog input channel 8 is read, 1 is written to both dynamic digital output
lines.
Channel List
Dynamic Digital
Values
Dynamic Digital
Outputs
Line 1 Line 0
5
6
7
8
2
0
1
3
1
0
0
1
0
0
1
1