FB_EcGetSlaveCount
The function block FB_EcGetSlaveCount can be used to determine the number of slaves that are connected to the master.
VAR_INPUT
VAR_INPUT
sNetId : T_AmsNetId;
bExecute : BOOL;
tTimeout : TIME := DEFAULT_ADS_TIMEOUT;
END_VAR
sNetId: This is a string that contains the AMS network identifier of the EtherCAT master device.
bExecute: The block is activated by a rising edge at this input.
tTimeout: Maximum time allowed for the execution of the function block.
VAR_OUTPUT
VAR_OUTPUT
bBusy : BOOL;
bError : BOOL;
nErrId : UDINT;
nSlaves : UINT;
END_VAR
bBusy: This output is set when the function block is activated and remains set until an acknowledgement is received.
bError: This output is set up after the bBusy output has been reset if there has been an error in transmission of the command.
nErrId: Supplies the ADS error code associated with the most recently executed command if the bError output is set.
nSlaves: The number of slaves that are connected to the master.
Example of an implementation in ST:
PROGRAM TEST_GetSlaveCount
VAR
fbGetSlaveCount : FB_EcGetSlaveCount;
sNetId : T_AmsNetId := '172.16.2.131.2.1';
bExecute : BOOL;
nSlaves : UINT;
bError : BOOL;
nErrId : UDINT;
END_VAR
fbGetSlaveCount(sNetId:= sNetId, bExecute:=bExecute);
nSlaves:=fbGetSlaveCount.nSlaves;
bError:=fbGetSlaveCount.bError;
nErrId:=fbGetSlaveCount.nErrId;
Requirements
Development environment | Target system type | PLC libraries to be linked |
---|---|---|
TwinCAT v2.10.0 or higher | PC or CX (x86) | TcEtherCAT.lib |
TwinCAT v2.10.0 Build >= 1301 or higher | CX (ARM) |