Sequencing Example 2, Dl430 - Automation Direct DL405 User Manual

12–18
F4–04DA 4-Channel Analog Output
Sequencing
Example 2,
DL430
4 4 4
430 440 450
Since the DL430 does not support the OUTF instruction, the previous program
must be modified to make sure the channel select bits are not accidentally changed
by the data in the accumulator. It is important to use the rungs in the order shown for
the program to work. This example will also work with DL440 and DL450 CPUs.
Ch4. Done
C4
Ch3. Done
C3
Ch2. Done
C2
Ch1. Done
C1
Restart
C0
C1 C2 C3 C4
SP1
Select Channel 1
C1
C2 Select Channel 2
C3
Select Channel 3
C4 Select Channel 4
When channel 4 has been updated, C0 restarts the
C0
update sequence.
OUT
When channel 3 has been updated, this rung loads
LD
the data for channel 4 into the accumulator. By
V3004
turning on C4, this triggers the channel update (see
the channel select rungs below).
C4
OUT
When channel 2 has been updated, this rung loads
LD
the data for channel 3 into the accumulator. By
V3003
turning on C3, this triggers the channel update (see
the channel select rungs below).
C3
OUT
When channel 1 has been updated, this rung loads
LD
the data for channel 2 into the accumulator. By
V3002
turning on C2, this triggers the channel update (see
the channel select rungs below).
C2
OUT
This rung loads the data for channel 1 into the
LD
accumulator. C0 restarts the sequence after
V3001
channel 4 is done (see the top rung). The first scan
or any interruption in control relay sequencing is
C1
detected when control relays C1 through C4 are off.
OUT
In this case, we also start the sequence with
channel 1.
This rung converts the accumulator data to binary
BIN
(you must omit this step if you've already converted
the data elsewhere). The ANDD instruction masks
off the channel select bits to prevent an accidental
ANDD channel selection. The OUT instruction sends the
KFFF
data to the module. Our example starts with
V40501, but the actual value depends on the
location of the module in your application.
OUT
V40501
Y34 When the output selection bit is on (Y34 – Y37 in
this case), the module maintains that channel at its
OUT
current value. If the output selection bit is off, the
corresponding channel is updated with the data
Y35
from the accumulator.
OUT
Output Channel
Y34 Ch. 1
Y36
Y35 Ch. 2
OUT
Y36 Ch. 3
Y37 Ch. 4
Y37
OUT