Elatec TWN4 MultiTech 2 HF Release Note

TWN4 MultiTech 2 BLE
Technical Handbook
DocRev2, July 7, 2017
Elatec GmbH

Contents
Contents
1.Introduction .............................................. 3
2. TWN4 MultiTech 2 BLE PCB . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
2.1. Functional Overview . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 4
2.2. Dimensions and Pinout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 5
3. Bluetooth Low Energy (BLE) Feature . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
4. Power states and current consumption breakdown . . . . . . . . . . . . . . . . . . . . . . . . . 8
5.Disclaimer............................................... 10
6. Bibliography . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
A. Appendix: Connector Pinout Reference . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 12
B. Appendix: BLE Technical Information . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 13
Page 2of 14

1. Introduction
1. Introduction
The TWN4 MultiTech 2 BLE Module is a configurable Reader/Writer of RFID transponders. This addition to
the TWN4 family offers the Bluetooth Low Energy (BLE) interface. The Module has both the low (125kHz,
134.2kHz) and high (13.56MHz) frequency antennas, allowing the User access to a wide range of RFID
standards.
This Technical Handbook provides the details needed to get started using the TWN4 MultiTech 2 BLE.
We begin with a functional overview of the board, listing the features and interface options available. We
then proceed with short introduction to the BLE Standard itself and the details of its implementation on the
board.
The custom User App can be loaded onto the module using the AppBlaster software. For more information
regarding the programming of the TWN4 module please see a dedicated User Guide for AppBlaster.
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2. TWN4 MultiTech 2 BLE PCB
2. TWN4 MultiTech 2 BLE PCB
2.1. Functional Overview
The TWN4 MultiTech 2 BLE is a complete RFID Reader system that requires a 5V power source and con-
nection to host to work. The majority of the circuitry responsible for processing the RFID card information
and executing the module firmware is shielded as shown on Figure 2.1. The device can be connected
to the host via USB or UART interface; both use the same connector (DF11). The cable can be simply
connected with no extra configuration required. The pinout for the DF11 connector is described in Table
A.1. A more generic breakout interface to the main controller is available; its pinout is shown on Table A.2.
The TWN4 MultiTech 2 BLE also offers 2 SAM slots and a speaker on board.
The TWN4 MultiTech 2 BLE can also interact with the User via Bluetooth Low-Energy interface. This
development pack contains documentation on BLE protocol and API implemented on the module.
Figure 2.1.: TWN4 MultiTech 2 BLE View Functional
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2. TWN4 MultiTech 2 BLE PCB
2.2. Dimensions and Pinout
Figure 2.2 provides the physical dimensions of the TWN4 MultiTech 2 BLE.
Figure 2.2.: PCB Dimensions
Page 5of 14

2. TWN4 MultiTech 2 BLE PCB
The module provides a generic access port that allows the User to bypass the main DF11 connector and
interact with the TWN4 MultiTech 2 BLE microcontroller directly. The port name is DRP2 and the polarity
of its pins is shown on Figure 2.3. The pinout is provided in Table A.2.
Figure 2.3.: PCB Dimensions
Page 6of 14

3. Bluetooth Low Energy (BLE) Feature
3. Bluetooth Low Energy (BLE) Feature
The traditional Bluetooth standard is convenient for constant-flow media transfer applications such as video
streaming. The Bluetooth Low Energy standard was introduced for applications requiring a lower power
consumption profile. Data is sent in bursts, followed by periods of electrical idle.
The TWN4 MultiTech 2 BLE uses the BGM111 module from Silicon Labs. The chip implements the
Physical, Link and L2CAP Layers of the BLE Protocol. The API is implemented within the firmware of
the main TWN4 microcontroller. The 2 chips interact via the COM2 port of the microcontroller, thereby
rendering this port unavailable for custom user functions.
Devices supporting the BLE standard communicate using a protocol named Generic Attribute Profile
(GATT). GATT defines two roles: Server and Client. A GATT Server stores attributes of the device and
sends them to a Client upon request. The TWN4 MultiTech 2 BLE acts as a GATT server, receiving re-
quests for information from the link partner (ex. cellphone) and transmitting relevant attributes back.
Some attributes are pre-defined by the Bluetooth standard; they include the General Access Profile and De-
vice Information. This information is read-only and is used for identification of the device. In the case of the
TWN4 MultiTech 2 BLE module, these read-only attributes are listed in Table B.1. The UUID identifies the
attribute in a global sense; this is the ID that the GATT Client (cellphone) sees. The Attribute Handle is what
is used within the Application running on the TWN4 microcontroller. When a request for a certain UUID
comes from outside TWN4, the App running on TWN4 microcontroller requests this information from the
BGM111 module using the Attribute Handle (See API command BLEGetGattServerAttributeValue).
Developers are free to introduce custom product-specific attributes with variable (read-only, read/write)
permissions. In the case of the TWN4 MultiTech 2 BLE module, the Generic Attribute service is introduced
(Table B.2). This is the method by which a GATT Client can obtain RFID card information from the TWN4.
The GATT Client (cellphone) makes a request for a custom-defined UUID (see Table B.3). This triggers a
request for the Generic Attribute service from the BLE module. The RFID data is then sent from the BLE
module to the TWN4 microcontroller and subsequently to the GATT Client.
The list of available attribute handlers is not sent to the GATT Client at any point, and no command is
available to request it. The UUIDs must be pre-programmed into the GATT Client in advance. This is
not an issue for Bluetooth-defined UUIDs such as Device Information, but is something to be aware of
regarding the custom-defined attributes.
For more information regarding the Bluetooth Low Energy Standard please see document "Designing for
Bluetooth Low Energy"[1] from Silicon Labs.
For the description of all the BLE-related commands available, please see the TWN4 API document.
Page 7of 14

4. Power states and current consumption breakdown
4. Power states and current consumption
breakdown
The TWN4 MultiTech 2 BLE supports 3 power states that can be used to reduce the current consumption
of the reader when the application calls for it.
In Normal state the reader can accommodate a request to search for a high-/low-frequency tag, perform
a BLE action or interact with peripherals on short notice; the current consumption in this state is the
highest.
In Sleep state the reader is not capable of any of the above, but consumes considerably less current. The
reader can be woken by communication on USB/COM ports, predefined timeout, or a Low-Power-Card-
Detection (LPCD) event and taken to Normal state.
In Stop state the reader consumes the least current and can be woken up via external/internal interrupt, or
a Low-Power-Card-Detection (LPCD) event and taken to Normal state.
Changing the LPCD poll time will change the current consumption, which can be estimated with the fol-
lowing formula:
ILP CD = 0.5mA +0.1mAs
tP oll[s]
The first section of Table 4.1 shows the expected typical current draw in the 3 states described above,
depending on the reader interface used. The second section of the table lists the maximum additional
current drawn by the device’s peripherals; these values are to be added to those in the "Normal Idle" base
state. It is assumed that a +5V DC Power Source is used.
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4. Power states and current consumption breakdown
Host Connection USB UART-TTL
Typical Consumption in Base System States
Normal Idle 65 59
Sleep 15 6,8
Sleep LPCD Option 15,3 7,0
Stop N/A 0,45
Stop LPCD Option N/A 0,8
Maximum Consumption by Function wrt. Normal Idle System State
SearchTag-HF +140
SearchTag-LF +25
RS232 +4
BLE Active Packet Reception +9
BLE Active Transmission (0 dBm output power) +9
BLE Active Transmission (8 dBm output power) +24
Speaker Constant Tone +80
LED (Red) +2
LED (Green) +6
LED (Yellow) +8
Table 4.1.: Current Consumption Breakdown given +5V DC Supply (mA)
Page 9of 14

5. Disclaimer
5. Disclaimer
Elatec reserves the right to change any information or data in this document without prior notice. The
distribution and the update of this document is not controlled. Elatec declines all responsibility for the use
of product with any other specifications but the ones mentioned above. Any additional requirement for a
specific custom application has to be validated by the customer himself at his own responsibility. Where
application information is given, it is only advisory and does not form part of the specification.
All referenced brands, product names, service names and trademarks mentioned in this document are the
property of their respective owners.
Page 10 of 14

6. Bibliography
6. Bibliography
1. Silicon Labs Website. Application Note "Designing for Bluetooth Low Energy Applications", taken from
http://www.silabs.com on 24. January, 2017
Page 11 of 14

A. Appendix: Connector Pinout Reference
A. Appendix: Connector Pinout Reference
Pin Pin Name Function
1 UGND USB Ground. Fed to main Ground through noise-reduction circuit.
2 USB_D+ USB Data +
3 UVCC USB VCC (5V). When using RS232, connect this to external 5V supply.
4 USB_D- USB Data -
5 V24_RXD RS232 RXD (Input)
6 GND Ground
7 V24_TXD RS232 TXD (Output)
8 Hostsense Active-low, enables RS232 transceiver. Short to Pin 6 (GND) when using RS232.
Table A.1.: Main Interface DF11 Port (X2) Pin Configuration
Pin Pin Name Function
1 GND Ground
2 USB_D+ USB Data +
3 Supply 5V Powers the 5V circuitry on board. Input to 3.3V Regulator.
4 USB_D- USB Data -
5 VCC 3.3V Direct access to 3.3V supply net after Regulator. Microcontroller and majority of
circuitry is powered by this.
6 COM1_RX COM1 RX Single-ended port
7 I2C_SCL I2C Clock
8 COM1_TX COM1 TX Single-ended port
9 I2C_SDA I2C Data
10 GPIO3 direct access to microcontroller
11 RESET- Active-low reset to the microcontroller
12 GPIO4 direct access to microcontroller
13 PWRDWN- Active-low powerdown to 3.3V Converter/Regulator
14 GPIO5 direct access to microcontroller
15 GPIO6 direct access to microcontroller
16 GPIO7 Active-low reset to BLE module
Table A.2.: Generic Interface DRP2 Port (X1) Pin Configuration
Page 12 of 14

B. Appendix: BLE Technical Information
B. Appendix: BLE Technical Information
UUID
(hex)
Attr.
Handle
Name R/W Type Description
1800 General Access Profile Service Service 1
2a00 7 Device name R Descriptor xgatt_1800_2A00,
fix "TWN4 BLE"
2a01 9 Appearance R Descriptor xgatt_1800_2A01,
fix 0000
180a Device Information Service Service 2
2a29 12 Manufacturer Name R Descriptor xgatt_180A_2A29,
fix "OEM BLE"
2a24 14 Model Number R Descriptor xgatt_180A_2A24,
"TWN4 MultiTech"
2a25 16 Serial Number R Descriptor xgatt_180A_2A25
2a26 18 Firmware Revision R Descriptor xgatt_180A_2A26,
f.e. "V1.04,16.05.2017"
Table B.1.: Read-only Bluetooth Standard-defined GATT Services
UUID
Name
Attr.
Handle
Name R/W Type Description
UID1 Generic Attribute Service Service 3
UID2 21 SPP Data Read,
Notify, Write
no response
Descriptor xgatt_spp_data
var. length=255,
HEX data.
UID3 24 SP1 Data Notify, Write
no response
Descriptor xgatt_sp1_data
var. length=20,
HEX data.
UID4 27 SP2 Data Indicate,
Read
Descriptor xgatt_sp2_data
var. length=20,
HEX data.
Table B.2.: Custom GATT Services defined within Firmware
Page 13 of 14

B. Appendix: BLE Technical Information
UUID
Name
User UUID (hex) Description
UID1 "5a44c004-4112-4274-880e-cd9b3daedf8e" SPP Service
UID2 "43c29edf-2f0a-4c43-aa22-489d169ec752" xgatt_spp_data
UID3 "a897339f-adf0-4a2b-a2ef-4a57512e6eb6" xgatt_sp1_data
UID4 "71f1ae4d-e1d1-438c-b05d-2c2c16abeaa7" xgatt_sp2_data
Table B.3.: Definition of Custom UUIDs
Page 14 of 14