AutomationDirect DL105, User Manual

Page: 90 / 350

High
-S
peed
Input
and
Pulse
O
utput
Features
3--14
High-speed Input and Pulse Output Features
DL105 PLC User Manual, 3rd Edition
UDC
CT76
Kxxxxxxxx
SP1
SP1
SP1
END
END coil marks the end of the main program.
INT O0
CT76 is the HSIO counter. The first rung’s SP1
always enables the counter. The preload contact in
the middle is off (unused in this example).
IRT
Return from the interrupt service routine.
Y0 SP540
Inside the interrupt service routine, we turn OFF the
lead screw motor immediately.
The INT label marks the beginning of the interrupt
service routine program.
RST
X4
RST
Input X4 energizes when the groove has finished
cutting. So, we retract the cutter head.
Y1
X5
SET
Turn lead screw on again, after cutter head has
retracted.
Y0
LDD
K4850
Load the preset C value into the accumulator.
OUTD
V2324
Output the accumulator contents to the memory
location for preset 3.
LDD
Kffff
Load the constant Kffff into the accumulator. This
value represents the end of the preset list.
OUTD
V2326
Output the accumulator contents to the memory
location for preset 4 (end of preset marker).
SP541
SP542
These special “equal” relays turn on individually as
the corresponding preset is reached. In this
application, each results in the cutting of a groove
(Y1), so they are logically ORed together.
Preset 1
Preset 2
Preset 3
SET
Y1
SP0
X2
SET
Input X2 will be energized inside the interrupt
routine if X2 external interrupt was the source.
C10
The third rung’s Reset input is normally off,
because we will use the external reset. You can
optionally reset the counter value on each powerup
using the SP0 contact.
Some applications will require a different type of action at each preset. It is possible
for the interrupt routine to distinguish one preset event from another, by turning on a
unique output for each equal relay contact SPxxx. We can determine the source of
the interrupt by examining the equal relay contacts individually, as well as X2. The X2
contact will be on (inside the interrupt routine only) if the interrupt was caused by the
external reset, X2 input.