Automation Direct DL405 User Manual page 371

Sequencing The next three example programs show you how to send digital values to the
the Channel module when you have more than one channel. The first two examples will
Updates automatically update all four channels over four scans, while the last example
updates all four channels in one scan.
The first sequencing example is fairly simple and will work in almost all situations.
We recommend it for new users. It uses control relays C1 through C4 as index
numbers corresponding to the channel updated on any particular scan. At the end
of each scan, only one control relay C1 through C4 is on. On each subsequent
scan, the next control relay energizes. The channel sequencing automatically
begins with channel 1 on the first scan, or after any disruption in the logic.
The second example is slightly more complex. However, it does not depend on the
use of control relays to provide channel sequencing. Instead, it uses function boxes
to increment a channel pointer value in V-memory. Then, other instructions perform
bit manipulations to position the channel select bits properly in the output word to
the module.
In the last example, we show you how you can update all four channels in the same
scan with D4–440 and D4–450 CPUs. However, this can increase the scan time
and you may not always need to update all four channels on every scan.
F4–04DAS–2 4-Channel Isolated 0–5V, 0–10V Output
18–13