Wurth Elektronik THETIS-I User manual

THETIS-I MINI EVALUATION BOARD USER
MANUAL
FOR RADIO MODULES
EV Order Code Module order code Product Name
2611109021011 2611011021010 Thetis-I
VERSION 1.0
FEBRUARY 12, 2021

***************
MUST READ
Check for firmware updates
Before using the product make sure you use the most recent firmware version, data sheet
and user manual. This is especially important for Wireless Connectivity products that were
not purchased directly from Würth Elektronik eiSos. A firmware update on these respective
products may be required.
We strongly recommend to include in the customer system design, the possibility for a
firmware update of the product.

Revision history
Manual
version
HW
version Notes Date
1.0 1.0 • Initial version February 2021
Thetis-I Mini Evaluation Board user manual version 1.0 © February 2021
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Abbreviations and abstract
Abbreviation Name Description
API Application Programming Interface
COG Chip on Glass
COM Port Communication Port
CSAP Configuration Service Access Point UART control command for module
configuration
DSAP Data Service Access Point UART control command for radio
data transmission and reception
EV Evaluation
ESD Electro Static Discharge
FCC Federal Communications
Commission
FTDI Future Technology Devices
International USB-to-Serial converter chip
GND Ground Ground signal level that corresponds
to 0 V
HIGH High signal level
IO Input & Output
JTAG Joint Test Action Group
LDO Low Dropout
LED Light Emitting Diode
LFCLK Low frequency clock
LFXO Low frequency crystal oscillator
LOW Low signal level
MCU Micro Controller Unit
MSAP Management Service Access Point UART control command for module
management
NPO Negative-Positive 0
OTA Over the air
PC Personal Computer
PCB Printed Circuit Board
RF Radio frequency Describes everything relating to the
wireless transmission.
RSVD Reserved
SMA SubMiniature version A
SMD Surface-Mount Device
SWD Serial Wire Debug
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THT Through-hole technology
TTL Transistor-Transistor Logic
UART Universal Asynchronous Receiver
Transmitter
Universal Asynchronous Receiver
Transmitter allows communicating
with the module of a specific
interface.
USB Universal Serial Bus
VDD Voltage Drain Drain Supply voltage
WE Wuerth Elektronik
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Contents
1 Supported radio modules 6
2 Functional description 7
2.1 Taking into operation - PC . . . . . . . . . . . . . . . . . . . . . . . . . . . . 7
2.2 Taking into operation - Host controller . . . . . . . . . . . . . . . . . . . . . 9
3 Development board - Thetis-I mini evaluation board 10
3.1 Blockdiagram................................... 10
3.2 Connectors and pin headers . . . . . . . . . . . . . . . . . . . . . . . . . . . 11
3.2.1 P1, P2, P3: Module access pins . . . . . . . . . . . . . . . . . . . . 13
3.2.2 P3: TTL-232R-3V3 FTDI cable connector . . . . . . . . . . . . . . 13
3.2.3 P4, P5: Alternative power supply connection . . . . . . . . . . . . . 14
3.2.4 JTAG Debugging Interface . . . . . . . . . . . . . . . . . . . . . . . 14
3.2.5 SMA ................................... 15
3.3 Jumpers...................................... 17
3.3.1 JP1.................................... 18
3.3.1.1 JP1: Power LED separation . . . . . . . . . . . . . . . . . . . . 18
3.3.1.2 JP1: Power supply selection . . . . . . . . . . . . . . . . . . . . 18
3.4 Resetbutton ................................... 19
3.5 Functionblocks.................................. 20
3.5.1 Powersupply .............................. 20
3.5.1.1 Connector P3, power supply through TTL-232R-3V3 . . . . . . 20
3.5.1.2 Connector P3, power supply through external source . . . . . . 20
3.5.1.3 Connectors P4 and P5, power supply through external source . 20
3.5.2 UART/USB............................... 20
3.5.3 UARTdirect ............................... 20
3.5.4 LFXOcrystal .............................. 21
3.5.4.1 LFXO Design guidelines . . . . . . . . . . . . . . . . . . . . . . 22
3.5.5 Programming interface . . . . . . . . . . . . . . . . . . . . . . . . . 22
3.6 Schematic..................................... 23
3.7 Layout....................................... 24
4 References 26
5 Regulatory compliance information 27
5.1 EuropeanConformity............................... 27
5.2 FCC ........................................ 27
5.3 Exemptionclause................................. 27
6 Important notes 28
6.1 General customer responsibility . . . . . . . . . . . . . . . . . . . . . . . . . 28
6.2 Customer responsibility related to specific, in particular safety-relevant ap-
plications ..................................... 28
6.3 Best care and attention . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
6.4 Customer support for product specifications . . . . . . . . . . . . . . . . . . 28
6.5 Productimprovements.............................. 29
6.6 Productlifecycle ................................. 29
6.7 Propertyrights .................................. 29
6.8 General terms and conditions . . . . . . . . . . . . . . . . . . . . . . . . . . 29
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7 Legal notice 30
7.1 Exclusionofliability................................ 30
7.2 Suitability in customer applications . . . . . . . . . . . . . . . . . . . . . . . 30
7.3 Trademarks .................................... 30
7.4 Usagerestriction ................................. 30
8 License terms 32
8.1 Limitedlicense .................................. 32
8.2 Usageandobligations .............................. 32
8.3 Ownership..................................... 33
8.4 Firmwareupdate(s)................................ 33
8.5 Disclaimerofwarranty .............................. 33
8.6 Limitationofliability................................ 33
8.7 Applicable law and jurisdiction . . . . . . . . . . . . . . . . . . . . . . . . . . 34
8.8 Severabilityclause ................................ 34
8.9 Miscellaneous................................... 34
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1 Supported radio modules
The evaluation board described in this manual is exclusively for the Thetis-I module:
Order code Product Name Description
2611011021010 Thetis-I Wirepas Mesh 2.4 GHz radio module with smart
antenna configuration
Order code Product Name
2611109021011 Mini EV Board Thetis-I
Table 1: Compatibility
Content 2611109021011 Quantity
Thetis-I mini evaluation board 1
Packaging: ESD safe cover 1
Table 2: Content Thetis-I Wirepas Mini EV Board
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2 Functional description
The Thetis-I mini evaluation board is an application-oriented development board meant to
support the rapid prototyping of a Wirepas mesh network. It offers the user the possibility to
develop hardware and software for the Thetis-I Wirepas module.
By default, the basic pin headers and connectors are assembled in the mini evaluation board.
The additional components shall be assembled by the user according to requirements and
application.
The addional assembly is intended for experienced developers, as additional accessories
and basic soldering skills are necessary to take the board into operation.
Accessories required:
• Additional assembly components listed in the table 4 .
• Soldering equipment
• (Optional) TTL-232R-3V3 FTDI cable
For the connection to a micro controller or PC the evaluation board is equipped P3 Pin head-
er which is connected to the pins of the radio module. The additional pin headers can be
soldered to the placeholders to access the module pins. Jumpers allow the power selection
and current measurement of the module.
The mini evaluation board can be connected to an USB port of a PC using TTL-232R-3V3
FTDI cable.
2.1 Taking into operation - PC
To take the mini evaluation board into operation using a PC, pin header P3 shall be used.
The corresponding FTDI driver package (www.ftdichip.com/Drivers/VCP.htm)
has to be installed on the PC. The installation guidelines shall be followed:
(https://www.ftdichip.com/Support/Documents/InstallGuides.htm)
To take the mini evaluation board into operation, please perform the following steps:
1. Connect the evaluation board to the PC
a) Connect the TTL-232R-3V3 FTDI cable to the connector P3 of the evaluation
board.
Incorrect orientation of TTL-232R-3V3 FTDI cable will damage the radio mod-
ule.
b) Then connect TTL-232R-3V3 FTDI cable to the USB port of the PC. In that way
a COM port can be detected and installed on the PC. In the device manager the
COM port name of the TTL-232R-3V3 FTDI cable can be found. A COM port
shall appear for example: "COM12" in Windows systems or "/dev/ttyUSB0" in
Linux systems.
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2. Configure the mini evaluation board as sink
a) Open the Wirepas Commander PC tool, available for free download at this page:
https://www.we-online.com/web/en/electronic_components/produkte_pb/SW
b) Select the right COM port of the Thetis-I evaluation board and press the "Open/-
Close COM port" button.
Figure 1: Open COM port
c) Configure the connected Thetis-I evaluation board as sink of the network: go to
the "CSAP" tab and set
• the node address to a unique address.
• the address of the network to 7.
• the channel of the network to 39.
• the node role to "SINK".
Figure 2: Configure the sink
d) Start the radio stack on the "MSAP" tab.
Figure 3: Start the sink
3. To make other Thetis-I mini evaluation board units join this Wirepas network, connect
them to the PC in the same way.
4. Configure these mini evaluation boards as routing nodes taking part in the Wirepas
network consisting of the previously configured sink device.
a) Open further instances of the Wirepas Commander.
b) Select the right COM port of the Thetis-I evaluation board and press the "Open/-
Close COM port" button (see figure 1 ).
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c) Configure the connected Thetis-I mini evaluation boards: go to the "CSAP" tab
and set
• the node address to a unique address (for the sink we used 0 in the example,
thus do not use 0 here for the routing node).
• the address of the network to 7.
• the channel of the network to 39.
• the node role to "ROUTER_NODE".
d) Start the radio stack on the "MSAP" tab (see figure 3 ).
e) To transmit data from the Wirepas mini evaluation board to the sink enter the data
you want to transmit in the fields of the "DSAP" tab. As destination node address
type "sink".
Figure 4: Transmit data to the sink
All details about the UART interface can be found in the Wirepas dual MCU manual [1] and
the Thetis-I manual: https://www.we-online.de/catalog/en/WIREPAS_MODULE.
2.2 Taking into operation - Host controller
To take the mini evaluation board into operation using a host controller, pin header P3 shall
be used.
An external power supply shall be connected to the evaluation board. The power supply op-
tion 2 or 3 from the table 15 shall be used. It is important that the VDD is stable and able to
reliably supply the module’s static and peak current consumption as specified by the module
manual.
The next step is to connect the communication lines of the module to the host controller. The
headers P1, P2 and P3 can be used to connect the module pins to the host.
All details about the UART interface can be found in the Wirepas dual MCU manual [1] and
the Thetis-I manual. A free C implementation of the Wirepas Dual MCU API is available at:
https://github.com/wirepas/c-mesh-api.
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3 Development board - Thetis-I mini evaluation board
3.1 Block diagram
TTL-232R-3V3
FTDI cable
(5V Power
Supply)
5V to 3V
Voltage
regulator Thetis-I Wirepas module
2.54mm
pin header
P3 (1X6)
Reset
Button
2.54mm pin headers
(Access to module pins)
50Ω port to
λ/4 antenna
Mini evaluation
board
RF Filter &
50Ω matching Internal
Antenna
LEDs
Current
Measurement /
Solderbridge
2.54mm pin
header
Connector
(VDD, GND)
SMA Connector
THT
Alternate
power supply
(3V)
UART
(3.3V logic)
3V
5V
External
crystal
Figure 5: Block diagram
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3.2 Connectors and pin headers
Figure 6: Connectors and pin headers
The table 3 lists the pin headers assembled on the evaluation board by default. All the com-
ponents listed in the table 4 are SMD components.
Pin header Function Pins WE article number
P3 TTL-232R-3V3 FTDI cable
connection / Access to module pins 1X6 61000618321
P5 External power supply GND 1X4 61000418321
P4 External power supply 3V 1X4 61000418321
JP1 Power supply selection 1X6 61000618321
Table 3: Default assembled connectors
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The table 4 lists the optional components for the evaluation board. Most of the components
are common THT components that can be soldered on manually by the user.
Placeholder Function Pins WE article number
P1 Module access pins 1X5 61300511121
P2 Module access pins 1X9 61300911121
CON1 SMA Connector SMD 60312102114405
CON2 JTAG Connector 2X10 61302021121
Table 4: Additional assembly components
Based on the necessity the required components shall be assembled.
Holes with 2mm diameter on all the four corners are available for spacer or
standoff connections
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3.2.1 P1, P2, P3: Module access pins
P1 nRF52840 Function
1 P0.02 /DATA_IND
2 P0.18 RESET
3 SWDIO SWDIO
4 SWCLK SWCLK
5 GND
Table 5: Pin header P1
P2 nRF52840 Function
1 P0.19 LED1
2 P0.22 LED2
3 P0.09 B1, RSVD
4 P0.10 B2, RSVD
5 P0.23 B3, RSVD
6 P1.00 B4, RSVD
7 P0.21 B5, RSVD
8 P0.07 B6, RSVD
9 P0.03 17, RSVD
Table 6: Pin header P2
3.2.2 P3: TTL-232R-3V3 FTDI cable connector
P3 nRF52840 Function
1 GND
2 P0.11 15, RSVD
3 5V
4 P1.09 URXD
5 P1.08 UTXD
6 P0.12 16, RSVD
Table 7: Pin header P3
Pin header P3 is used to connect the TTL-232R-3V3 FTDI cable. P3 can also
be used for direct host connection.
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3.2.3 P4, P5: Alternative power supply connection
P4 Connection
1,2,3,4 3V External power supply
Table 8: Pin header P4
P5 Connection
1,2,3,4 GND
Table 9: Pin header P5
All the information related to the power supply are described in the chapter 3.5.1 .
3.2.4 JTAG Debugging Interface
JTAG Pin Function JTAG Pin Function
1 VDD 2 Not connected
3 Not connected 4 GND
5 Not connected 6 GND
7 SWDIO 8 GND
9 SWCLK 10 GND
11 Not connected 12 GND
13 Not connected 14 GND
15 RESET 16 GND
17 Not connected 18 GND
19 Not connected 20 GND
Table 10: JTAG debugging interface
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3.2.5 SMA
In order to use an external antenna, the SMA connector and relevant capacitors shal-
l be assembled. The 2.4GHz antenna Himalia from Würth Elektronik eiSos (order code
2600130021) is a perfect match: https://www.we-online.de/katalog/en/WIRL_ACCE_2600130021
By default the internal PCB antenna is used.
SMA Connection
Inner Module RF pin
Outer GND
Table 11: Pin header SMA
In order to use an external SMA antenna, 22 pF capacitor (0402) on position
C1 shall be assembled. C2, C8, C11 and C12 should be left unpopulated.
Optional: Experts have the possibility to use C11, C1 and C8 for additional
filtering or fine tuning.
Figure 7: Capacitor connection to internal antenna
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Figure 8: Capacitor connection to external antenna
In order to use the internal PCB antenna of the module, a 2.4 nH inductor
(0402) on position C2 and a 0.3 pF capacitor (0402) on position C12 shall be
assembled respectively. C1, C8 and C11 should be left unpopulated.
Optional: Experts have the possibility to use C2, C8 and C12 for additional
filtering or fine tuning.
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3.3 Jumpers
Figure 9: Jumpers
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3.3.1 JP1
JP1 pin header is assembled by default.
JP1 Function
1 VDD
2 LED Power
3 Not connected
4 3V LDO Output
5 VDD
6 3V External Power supply
Table 12: Pin header JP1
3.3.1.1 JP1: Power LED separation
JP1 Function Jumper set(default)
1<->2 Power LED sourced by VDD Yes
Table 13: Pin header JP1 Power LED
3.3.1.2 JP1: Power supply selection
JP1 shall be set to choose either internal on-board LDO or the external 3V as power supply.
The power LED is connected to the VDD line by the 1-2 pins of JP1. To mea-
sure module current consumption, the jumper JP1 (1<->2 pins) shall be re-
moved.
.
JP1 Function Jumper set(default)
4<->5 External 3V power supply No
5<->6 Internal LDO power supply Yes
Table 14: Pin header JP1 Power supply selection
On JP1 a current meter shall be connected instead of a jumper to measure the
current consumption of the module.
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