Automation Direct D0-DCM, Руководство пользователя

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Getting Started
User Application
Guidelines
RLL
Programming
for Communications
4–12
RLL Programming for Communications
DL05/06 Data Communications Module, 1st Edition, 08/05
OUT
C0
X0
In our example, the normally open contact
labeled X0 is a toggle switch input to a
discrete input module. When X0 is on,
Control Relay C0 is energized.
SET
SP123
Y1
The second rung uses a Special Relay to
identify a communication error. In the
example, SP123 is on if there is a
communication error present in slot 2. Use
different Special Relays if your DCM
module is in a different slot (see page 4-8).
We use SP123 to turn on an indicator light
connected to a discrete output.
LD
K214
LD
K2
LDA
O40600
WX
VC100
SP122
The Special Relay labeled SP122 is on
when slot 2 is busy transmitting or
receiving. The Write instruction may take
longer than one PLC scan to complete. Use
this Special Relay to prevent overwriting the
previous Write instruction with each PLC
scan.
Number of bytes to be transferred.
Max = 128 bytes.
Beginning address in the in master PLC,
expressed as an octal number.
Beginning address in the slave PLC.
2 1 4 0
Slave # (Hex)
K
Upper Byte Lower Byte
Slave PLC
Master PLC
DCM Slot #
END
All DirectLOGIC PLCs use an END
statement to identify the final rung of the
main body of the program.
END
OUT
Y0
C100 This two-rung program resides in the slave
PLC’s CPU. Its function is simply to take
the C100 contact and convert it to a real
output, Y0.
Program for the
Master PLC:
Rung 1
Rung 2
Rung 3
Rung 4
Program for the
Slave PLC