Mitsubishi MELSEC LJ71C24, User Manual

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12 DEDICATED INSTRUCTIONS
1 For error codes relating to abnormal completion, refer to Chapter 15.
2 When setting "Word/byte units designation" by GX Works2, set the number of bytes
when bytes are designated and set the number of words when words are
designated.
3 The settings are done by either of the following:
• User : Data set by the user before executing the INPUT instructions.
• System : The CPU module stores the execution result of the INPUT instructions.
Function
(1) The function stores in the device designated in (D1) and succeeding devices the
data received with the nonprocedural protocol of the module designated in Un,
according to the control data of the device designated in (S) and succeeding
devices.
(2) When the number of data actually received exceeds the allowable receive data
count specified by (S)+3, only the receive data within the allowable receive data
count is stored, and the remaining receive data is discarded. (The dedicated
instructions are completed normally.)
In this case, the allowable receive data count is stored in the receive data count
((S)+2).
(3) Simultaneous execution of dedicated instructions
The following table shows the handling for when executing another instruction
during execution of the INPUT instruction or executing the INPUT instruction
during execution of another instruction in the same channel.
Instruction
1
Availability of
simultaneous execution
Handling of simultaneous execution
OUTPUT
PRR
⎯
INPUT
•
The next instruction will be ignored until the active instruction has been completed.
(However, simultaneous execution is available when channels to be used are not the same.)
CSET (the right column)
[When instructions are executed in order of INPUT CSET]
•
Dedicated instructions simultaneous execution error (7FF0
H
) occurs in the CSET instruction.
(However, simultaneous execution is available when channels to be used are not the same.)
[When instructions are executed in order of CSET INPUT]
•
Simultaneous execution is available.
PUTE
GETE
⎯
BUFRCVS
INPUT instruction and BUFRCVS instruction cannot be used at the same time.
(However, simultaneous execution is available when channels to be used are not the same.)
SPBUSY
⎯
UINI
•
Dedicated instructions simultaneous execution error (7FF0
H
) occurs in the dedicated
instruction attempted later.
: Available : Not available
1 Since the dedicated instructions shown below use a different
communication protocol from that for the INPUT instruction, they are not
used in the same channel.
• ONDEMAND, BIDOUT, BIDIN, CPRTCL
If the dedicated instructions shown above are used in the same channel
with the INPUT instruction, the communication protocol setting error
(7FF2
H
) occurs.