CANopen Communication
FC5101 and FC5102
58
Version: 2.0
Fig. 45: SDO Read via ADS
SDO_READ(
StartReading :=ReadStart,
CO_Index :=16#1000,
CO_SubIndex :=16#0,
DataLength := 4,
PortNr := 16#1001,
ADSNetID:='192.168.10.11.2.1'
);
IF SDO_READ.ReadDataAvailable THEN
ReadStart :=FALSE;
ReadError :=SDO_READ.Error;
ReadData :=SDO_READ.ReadData;
END_IF
The SDO_READ function block that has been called in turn calls the ADSREAD function a number of times.
It looks like this (starting with the variable declaration):
FUNCTION_BLOCK SDO_READ
VAR_INPUT
ADSNetID:STRING(23); (* The AMSNetID addresses the FC5101 card. Can be empty if only one local s
ingle channel card is present*)
PortNr:WORD; (*This Port No. addresses the CANopen Node (see System Manager)*)
CO_Index:DWORD; (*This is the Index of the CANopen Object Dictionary Entry*)
CO_SubIndex:DWORD; (* This is the Sub-Index of the CANopen Object Dictionary Entry*)
DataLength:DWORD; (* This is the Length of the CANopen Object Dictionary Entry*)
StartReading:BOOL; (* only reset to FALSE after ReadDataAvailable=TRUE*)
END_VAR
VAR_OUTPUT
ReadData:ARRAY[0..255] OF BYTE;
ReadDataAvailable:BOOL;
Error:DWORD;
END_VAR
VAR
state:BYTE := 0;
ADSREAD:ADSREAD;
END_VAR
CASE
state OF
0:
IF StartReading THEN
ReadDataAvailable := FALSE;
Error := 0;
ADSRead(
NETID:= ADSNetID,
PORT:= PortNr,
IDXGRP:= CO_Index,
IDXOFFS:= CO_SubIndex,
LEN:= DataLength,
DESTADDR:= ADR(ReadData),
READ:= TRUE,
TMOUT := T#1s
);
IF ADSRead.err THEN
state := 2;
ReadDataAvailable := TRUE;
Error := ADSRead.ErrId;
ELSE
state := 1;
END_IF
ELSE
ADSRead(
NETID:= ADSNetID,
PORT:= PortNr,
IDXGRP:= CO_Index,
IDXOFFS:= CO_SubIndex,
LEN:= DataLength,
DESTADDR:= ADR(ReadData),
READ:= FALSE,
