Omron NJ101-10 Series, User Manual

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IF ( (Trigger=TRUE) AND (DoSdoRead=FALSE) AND (_EC_MBXSlavTbl[1]=TRUE) ) THEN
DoSdoRead :=TRUE;
SdoObject.Index :=UINT#16#100A;
SdoObject.Subindex :=USINT#0;
SdoObject.IsCompleteAccess:=FALSE;
EC_CoESDORead_instance(
Execute:=FALSE,
ReadDat:=VersionInfo);
END_IF;
IF (DoSdoRead=TRUE) THEN
EC_CoESDORead_instance(
Execute :=
TRUE,
NodeAdr :=UINT#1,
SdoObj :=SdoObject,
TimeOut :=UINT#20,
ReadDat:=VersionInfo);
IF (EC_CoESDORead_instance.Done=TRUE) THEN
NormalEnd:=NoUINT#1;
ELSIF (EC_CoESDORead_instance.Error=TRUE) THEN
ErrorEnd :=EUINT#1;
END_IF;
END_IF;
// Detect when Trigger changes to TRUE.
// Execute EC_CoESDORead instruction.
// Initialize instance.
// Dummy
// Node address 1
// SDO parameter
// Timeout time: 2.0 s
// Read data
// Processing after normal end
// Processing after error end
6-2-3
Execution Timing of SDO Communications
SDO communications are executed in the system service time of the NJ/NX-series CPU Unit.
System services are executed in the period between execution of all of the tasks. Refer to the
NJ/NX-
series CPU Unit Software User's Manual (Cat. No. W501) for details on the execution timing of system
services.
6-2-4 Minimum Message Response Time for SDO Communications
The minimum message response time for SDO communications is the time from when the SDO com-
munications instruction is executed in the user program until execution of the instruction is completed.
When the instruction is executed in the user program, the master sends a frame to the slave in the
system service. When the slave receives the frame, it processes it. When the slave completes proc-
essing, the master receives a response from the slave to complete execution of the instruction.
Additional Information
The minimum message response time depends on the unused time in task execution, slave
SDO size, and slave SDO processing time. In the timing chart below, the time from when the
SDO communications instruction is executed until execution of the instruction is completed
should be used for reference only.
NX-series CPU Units
The calculation formula for the minimum message response time differs between when the task period
of primary periodic task is smaller than 4 ms and when the task period is 4 ms or longer.
6 Process Data Communications and SDO Communications
6-21
NJ/NX-series CPU Unit Built-in EtherCAT Port User's Manual (W505)
6-2
SDO Communications
6
6-2-3
Execution T
iming of SDO Communications