Baltech RFID reader
If a supported Baltech RFID stand-alone device is used, the TwinCAT PLC library can be used as interface.
Alternatively certain Beckhoff Control Panels or Panel PCs can be used. In these devices a RFID reader can be integrated as an option.
In this case an SDK containing the proprietary documentation is provided.
The functionality if the TwinCAT library is the same in both cases.
RFID reader settings
For smooth communication between controller and RFID readers, some settings need to be made before the system startup. These include, for example, the baud rate for the serial communication. The proprietary tool 'Baltech id-engine explorer' provided by the RFID reader manufacturer can be used to transfer these settings to the RFID reader. The tool can be used to carry out a function test to check whether the RFID device is recognized and whether the transponder cards are detected.
The following default settings are recommended for the data transmission:
Setting | Value |
|---|---|
Baud rate | 115200 baud |
Parity Bit | none |
Data bits | 8 |
Stop bit | 1 |
This matches the factory setting of the supported Baltech RFID devices. Other parameters can be set, if required. These must then also be adopted into the reader connection on the software side.
The baud rate of the readers can be changed with the tool 'Baltech id-engine explorer'. (See Baltech documentation: IdEngineExplorer.pdf)
 | The tool 'Baltech id-engine explorer' only runs under Windows XP. It is not available for Windows CE. The baud rate is therefore not configurable under Windows CE. |
| In the PLC a fast task is required for processing the incoming data. When connecting an RFID device to a COM port and a baud rate of 115200 baud, a cycle time of 1 ms is required. (see chapter Reader connection). |
| In order to configure the baud rate from the PLC, the following byte sequence can be transferred as a raw data block [ 0x 1C 00 09 06 00 01 03 00 02 xx xx - with xx xx representing the baud rate, e.g. 9600 baud: 96 units at 100 baud -> 0x 00 60 ]. Further information can be found in section "Low level communication". This is also possible under Windows CE, if a transfer with the currently set baud rate is possible. |
Usage of virtual serial COM ports (USB)
If the device is connected via USB, the corresponding Usb-To-Virtual-Com-Port driver must be installed. This driver is already installed if it is about a Beckhoff Panel-PC. The SDK of the RFID device contains the driver too. The virtual COM port is displayed in the Windows device manager.
The Beckhoff TwinCAT 'Serial Communication' is used for the communication to driver. But neither a device is added to TwinCAT System Manager nor a mapping is done. Further information is to be found in the Documentation for the PLC library serial Communication.
Handling of the RFID reader
The library supports the default settings for the Baltech communication. 'Host Operation' mode is supported. Other modes are not supported. The BRP (Baltech Reader Protocol) is used for internal access in 'Communication Mode' 'Normal Mode'. If raw data are sent via the low level communication option it is important to ensure that the above settings are correctly specified within the frame.
| Not all peculiarities of each supported RFID reader model can be mentioned here. Therefore you are referred to the manufacturer’s own documentation for more detailed information. |
Configuration
If encrypted transponder cards are used, the same key must be available in the RFID device. The Baltech RFID reader is configured once, i.e. the key only has to be specified once. For security reasons the key cannot be read from the device configuration. In line with the encryption of a transponder card a VHL file is stored in the device configuration. Several VHL files can be stored in order to be able to access different cards access without reconfiguration.
There are three options for transferring VHL file into the configuration of a RFID device.
Configuration type | Description |
|---|---|
Configuration card | A configuration can be transferred via a configuration card. This is the preferred option. |
'Baltech id-engine explorer' tool | This tool can be used to transfer a configuration into the memory of the Baltech RFID device. (see Baltech documentation: IdEngineExplorer.pdf) The tool 'Baltech id-engine explorer' only runs under Windows XP. It is not available for Windows CE. |
from the PLC | For Mifare Classic cards the transfer of a VHL file configuration can be programmed in the PLC program code. The command SetConfig transfers the configuration specified at the input in ST_RFID_ConfigIn. The structure of a Mifare card and the possible settings for key allocation are explained in ST_RFID_CfgStruct_BaltechMifVHLFile. (More detailed information about Mifare cards can be found in the Baltech document entitled Mifare.pdf) |
Transponders
Suitable transponder cards for Baltech RFID devices are available from several manufacturers. If cards with encryption are to be used, Baltech offers preconfigured cards for this purpose.