FB_EcGetScannedSlaves
The function block FB_EcGetScannedSlaves can be used to read a list of the currently available (scanned) slaves from the EtherCAT master object directory. To this end an online scan is executed, during which the EEPROMs of the EtherCAT slaves are read. The scanning process may take some time, depending on the number of connected slaves.
Inputs
VAR_INPUT
bExecute : BOOL;
sNetId : T_AmsNetId;
pArrEcScannedSlaveInfo : POINTER TO ARRAY[0..EC_MAX_SLAVES] OF ST_EcSlaveScannedData;
cbBufLen : UDINT;
tTimeout : TIME := DEFAULT_ADS_TIMEOUT;
END_VAR
Name | Type | Description |
|---|---|---|
bExecute | BOOL | The function block is activated by a positive edge at this input. |
sNetId | T_AmsNetId | String containing the AMS network ID of the EtherCAT master device. (Type: T_AmsNetId) |
pArrEcScannedSlaveInfo | POINTER TO ARRAY[0..EC_MAX_SLAVES] OF ST_EcSlaveScannedData | Address of an array of structures of type ST_EcSlaveScannedData, to which the data for each scanned slave are to be written. |
cbBufLen | UDINT | Maximum available buffer size (in bytes) for the data to be read |
tTimeout | TIME | Maximum time allowed for the execution of the function block. |
Outputs
VAR_OUTPUT
bBusy : BOOL;
bError : BOOL;
nErrId : UDINT;
nSlaves : UINT;
ND_VAR
Name | Type | Description |
|---|---|---|
bBusy | BOOL | This output is set when the function block is activated, and remains set until a feedback is received. |
bError | BOOL | This output is set after the bBusy output has been reset when an error occurs in the transmission of the command. |
nErrId | UDINT | Supplies the ADS error code associated with the most recently executed command if the bError output is set. Error 1798 (0x706) indicates a null pointer at the buffer address. Error 1797 (0x705) indicates inadequate buffer size. |
nSlaves | UINT | Returns the number of scanned slaves. |
Requirements
Development environment | Target platform | PLC libraries to include |
|---|---|---|
TwinCAT v3.1.0 | PC or CX (x86, x64, ARM) | Tc2_EtherCAT |