Omron SYSDRIVE 3G3RV, User Manual

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Communications Functions
6-
109
• Response
to the Inverter Status Read
The
response to the DSR message to request the Inverter status in register 002C Hex consists of the fol-
lowing
items.
Fig 6.71 R
esponse to DSR Message Read
n
Ladder Program
Connect
the PST and the Communications Board, and read the Communications Board system settings from
the
PST. Set the start/stop bits both to 1 bit, and data length to 8 bits.
Transfer
the created protocol to the Communications Board. The following example describes how to control
the
Inverter with this protocol.
n
Memory Allocations
Starting Communications and Status Signals
IMPORTANT
Before using this program in your system, be sure to check the word and data memory allocations and
change them if necessary so that there will be no word or data memory duplication.
This program will stop all communications if a communications error or fault occurs. Be sure to set H5-05 for
communications error detection selection to 1 (effective) and H5-04 for communications error detection
operation selection to 0 through 2 so that the system will stop with time-over detection.
Word Functions common to all Slaves
Inverter
control communications (continued when set to ON)
Communications
error output (on hold when a communications error
or
fault occurs
Communications
fault reset
a 03 l W 1N 1 2 c
0 3
Slave address (Set with <a>)
Function code (Write 10)
Inverter status data (Set with variable)
CRC-16 check (Set with <c>)
Set data
Number of bytes of attached data (Set with <l>)
a 03 c
The address data, constant data, and check code data are the same as the above.
l
The length is set in the length box. Insert the length by using the Insert icon. The length is the number of bytes of the
succeeding data (W(1N + 1), 2). The length is automatically set by the CX-Protocol.
W 1N 1 2
The Inverter’s actual data is to be sent. This example selects Variable and Write W () (ntlp: English reference
mistakenly(?) says Read R () here) and sets the operand. Set the data to 1N + 1 because the RUN command data
uses two bytes each from D + 1, D + 2, and D + 3. (ntlp: English reference mistakenly(?) says the RUN command data
uses four bytes each from D + 3, D + 6, and D + 9. here)
Set Edit Length to 0N + 2 so that it will be set to two bytes.