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CHAPTER2 PROFIBUS Unit
2-12 Remote command
When the remote register is used, the message command can be issued directly from the
sequencer (PLC). The high-ranked commands such as MOVD command (movement
command which directly specifies the position coordinates), which must use RS-232C
unit conventionally, can be easily executed. The method to use these commands is ex-
plained in this section.
2-12-1 Remote command specifications
The following functions are assigned to the remote register.
Status
Reserved
Command response
IWm+8
IWm+10
IWm+12
IWm+14
IWm+16
IWm+18
IWm+20
IWm+22
Execution command
Command option
QWn+8
QWn+10
QWn+12
QWn+14
QWn+16
QWn+18
QWn+20
QWn+22
OUTPUT (Remote
→
Master)
INPUT (Master
→
Remote)
Address
Description
Address
Description
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The remote command is executed by setting QWn+8 and QWn+10 with the com-
mand code desired to execute. When the controller receives the command, it will
execute the process, and inform the result (status) to the master sequencer (PLC) side
via IWm+8. When the command is ended, set QWn+8 to 0, and clear the status. After
the status is cleared, the next command can be executed.
■
The command is sometimes provided with options on the remote command. The
option data is set at QWn+12 to QWn+22. Since the number of options, size and
setting address of the command option are different in each command, refer to "2-12-
3 Remote command details (robot operation)" and the subsequent sections.
Similarly, some commands return the data to the master sequencer (PLC) side as the
response. In this case, the response data is set at IWm+12 to Wm+22. Like the com-
mand option, the number of options, size and setting address of the response data are
also different in each command.
* Even if the data is set at the register not defined as any command option when the command is executed, there is not
any problem. (It is unnecessary to clear the not-defined register to 0.). Moreover, the register which is not defined as
the response data is not influenced during the command execution, and the register content before the command
execution is held.
■
It is necessary to set the command option to the register at the same time when or
before the command desired to execute is set.
■
The data is set with the binary code. If the data size exceeds 16 bits (1 word), set the
data of the upper-ranked bit at the higher address. (Little endian)
Example: To set 12345678 (hexadecimal) at the register of QWn+12 and QWn+14,
set 1234 (hexadecimal) at QWn+14 and 5678 (hexadecimal) at QWn+12.
■
IWm+10 is the system reservation. When it is read, 0 is returned.
