Silicon Laboratories Wizard Gecko WGM110 Wi-Fi Wireless Starter... User manual

UG172: WGM110 Wi-Fi Module
Wireless Starter Kit User's Guide
A Silicon Labs Wireless Starter Kit for the WGM110 Wizard Gecko
Wi-Fi® Module is an excellent starting point to get familiar with the
device, and it provides all necessary tools for developing a Silicon
Labs wireless application.
The Wireless Starter Kit Mainboard contains sensors and peripherals enabling easy
demonstration of some of the WGM110's many capabilities. An on-board J-Link debug-
ger allows debugging of the attached radio board as well as providing a debug connec-
tion for external hardware.
A plug-in Radio Board contains the reference design for the WGM110 itself, including the
RF section and device-specific hardware.
WSTK MAINBOARD FEATURES
• Ethernet and USB connectivity
• SEGGER J-Link on-board debugger
• Supports debugging the attached radio
board or an external device
• Silicon Labs' Si7021 Relative Humidity and
Temperature sensor
• Ultra low power 128x128 pixel Memory
LCD
• User LEDs / Pushbuttons
• 20-pin 2.54 mm header for expansion
boards
• Breakout pads for direct access to radio
board I/O pins
• Power sources include USB and CR2032
coin cell.
BRD4320A RADIO BOARD FEATURES
• WGM110 Wizard Gecko Wi-Fi Module with
1 MB Flash and 128 kB RAM, with on-
board chip antenna, RF match.
• USB Micro-B connector offers device mode
support.
• MicroSD card slot.
EXPANSION BOARD FEATURES
• Accelerometer
• Buttons and LEDs
• Joystick
SOFTWARE SUPPORT
• Wizard Gecko Wi-Fi Software
• Wizard Gecko Wi-Fi SDK
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1. Introduction
The WGM110 Wizard Gecko Wi-Fi Module itself is featured on a Radio Board that forms a complete reference design, inluding the RF
section and other components.
The WGM110 Radio Board plugs directly into a Wireless Starter Kit Mainboard. The WSTK Mainboard features several tools for easy
evaluation and development of wireless applications. An on-board J-Link debugger enables programming and debugging on the target
device over USB or Ethernet. The Advanced Energy Monitor (AEM) offers real-time current and voltage monitoring. A virtual COM port
interface (VCOM) provides an easy-to-use serial port connection over USB or Ethernet. The Packet Trace Interface (PTI) offers invalua-
ble debug information about transmitted and received packets in wireless links.
All debug functionality, including AEM, VCOM and PTI, can also be used towards external target hardware instead of the attached radio
board.
To further enhance its usability, the WSTK Mainboard contains sensors and peripherals demonstrating some of the WGM110's many
capabilities.
The Wireless Starter Kit for WGM110 includes an add-on board (BRD8006A) that can be connected to the WSTK Mainboard expansion
header. The expansion board contains additional peripherals such as an accelerometer, buttons, LEDs, joystick and a footprint for an
I2C authentication device. To support software development for the Wizard Gecko WGM110 Wi-Fi Module, Silicon Labs also offers a
free SDK. The SDK includes BGTool™ which can be used to configure the WGM110 Module and test its functionality.
1.1 Radio Boards
A Wireless Starter Kit consists of one or more mainboards and radio boards that plug into the mainboard. Different radio boards are
available. Each featuring different Silicon Labs devices with different operating frequency bands.
Since the mainboard is designed to work with all different radio boards, the actual pin mapping from a device pin to a mainboard feature
is done on the radio board. This means that each radio board has its own pin mapping to the Wireless Starter Kit features such as
buttons, LEDs, the display, the EXP header and the breakout pads. Because this pin mapping is different for every radio board, it is
important that the correct document be consulted which shows the kit features in context of the radio board plugged in.
This document explains how to use the Wireless Starter Kit when the WGM110 Wi-Fi Module Radio Board (BRD4320A) is combined
with a Wireless STK Mainboard. The combination of these two boards is hereby referred to as a Wireless Starter Kit (Wireless STK).
1.2 Ordering Information
BRD4320A can be obtained as part of SLWSTK6120A Wi-Fi Module Wireless Starter Kit or as a separate radio board, SLWRB4320A.
Table 1.1. Ordering Information
Part Number Description Contents Notes
SLWSTK6120A Wi-Fi Module Wireless Starter Kit 1x BRD4001A Wireless Starter Kit Mainboard
1x BRD4320A WGM110 Wi-Fi Module Radio Board
1x BRD8006A Blue Gecko Module Kit Add-on Board
1x AA Battery Holder
1x USB Type A <-> USB Mini-B cable
1x USB Type A <-> USB Micro-B cable
Obsoleted
SLWRB4300A WGM110 Wi-Fi Module Radio Board 1x BRD4320A WGM110 Wi-Fi Module Radio Board
1.3 Getting Started
Detailed instructions for how to get started can be found on the Silicon Labs web pages:
http://www.silabs.com/start-wgm
UG172: WGM110 Wi-Fi Module Wireless Starter Kit User's Guide
Introduction
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2. Kit Hardware Overview
The layout of the WGM110 Wi-Fi Module Wireless Starter Kit is shown in the figure below.
WGM110
Module
Radio Board
Radio Board breakout pads
Radio Board breakout pads
1.28" Memory-LCD Display
Ultra-low power
128 x 128 pixel resolution
SPI interface
Ethernet RJ-45
J-Link Debugger
Virtual COM port
Packet Trace
Advanced Energy Monitoring
USB mini-B
J-Link Debugger
Virtual COM port
Packet Trace
Advanced Energy Monitoring
Coin Cell Holder
CR2032 Battery
Power Select Switch
BAT / USB / AEM
2x User Push Buttons 2x User LEDs Simplicity Connector
External targets:
Virtual COM port
Packet Trace
Advanced Energy Monitoring
Debug Connector
ARM Coresight 19-pin
OUT: External targets
IN: External debug probes
Reset Button
Si7021
Relative Temperature &
Humidity Sensor
EXP Header
Expansion board connector
Expansion Board
3-axis Accelerometer
2x Push Buttons
2x LEDs
Analog Joystick
I2C device footprint
microSD/SDHC card slot
On the bottom side of the Radio Board
Figure 2.1. Kit Hardware Overview
UG172: WGM110 Wi-Fi Module Wireless Starter Kit User's Guide
Kit Hardware Overview
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3. Kit Block Diagram
An overview of the WGM110 Wi-Fi Module Wireless Starter Kit is shown in the figure below.
WGM110
WiFi Module
USB Mini-B
Connector
RJ-45 Ethernet
Connector
Debug
UART
AEM
Multiplexer
Debug
UART
Packet Trace
AEM
Debug
UART
Packet Trace
AEM
Simplicity
Connector
Debug
Connector
User Buttons
& LEDs
128 x 128 pixel
Memory LCD
GPIO
Board
Controller
OUT
IN
MCU
I2C Si7021
Temperature
& Humidity
Sensor
SPI
ADC Input
GPIO
SPI
USB Micro-B
Connector
Micro-SD
card reader
Accelerometer
BMA280
Analog
Joystick
Buttons
&
LEDs
Footprint for
I2C security
device
I2C
USB
Debug
USB Mini-B
Connector
UART
RJ-45 Ethernet
Connector
AEM
Multiplexer
Debug
UART
ETM Trace
Packet Trace
AEM
Debug
UART
Packet Trace
AEM
Simplicity
Connector
Debug
Connector
Board
Controller
OUT
IN
MCU
WGM110
WiFi Module
Figure 3.1. Kit Block Diagram
UG172: WGM110 Wi-Fi Module Wireless Starter Kit User's Guide
Kit Block Diagram
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4. Connectors
This chapter gives you an overview of the Wireless STK Mainboard connectivity. The placement of the connectors can be seen in the
figure below.
Simplicity
Connector
In/Out Debug
Header
GND
GND
5V
5V
P25
P24
P27
P26
P29
P28
P31
P30
P33
P32
P35
P34
P37
P36
P39
P38
P41
P40
P43
P42
P45
P44
GND
GND
NC
NC
Radio Board
Connectors
Expansion
Header
GND
GND
VMCU
VMCU
P1
P0
P3
P2
P5
P4
P7
P6
P9
P8
P11
P10
P13
P12
P15
P14
P17
P16
P19
P18
P21
P20
GND
GND
P23
P22
VRF
VRF
3V3
3V3
Figure 4.1. Mainboard Connector Layout
4.1 Breakout Pads
Most of the WGM110's pins are routed from the radio board to breakout pads at the top and bottom edges of the Wireless STK Main-
board. A 2.54 mm pitch pin header can be soldered on for easy access to the pins. The figure below shows you how the pins of the
WGM110 maps to the pin numbers printed on the breakout pads. To see the available functions on each, please refer to the WGM110
Data Sheet.
GND
VMCU
P23 / NC
P21 / NC
P19 / NC
P17 / NC
GND
P15 / NC
P13 / PE0 / I2C_SDA
P11 / PD5
P9 / PD4
P7 / PD3
P5 / PD2 / SD_CLK / DISP_SCLK
P3 / PD1 / SD_MISO
P1 / PD0 / SD_MOSI / DISP_SI
GNDGND
5V5V
NCNC
P45 / NCNC / P44
P43 / NCNC / P42
P41 / NCNC / P40
3V33V3
P39 / PC15 / DISP_COMNC / P38
P37 / PC9 / SENSOR_ENNC / P36
P35 / PC14 / DISP_SCSNC / P34
P33 / PC13 / DISP_ENNC / P32
P31 / PD7 / SD_CSWIFI_CS / P30
P29 / PD6 / SD_CDWIFI_CLK / P28
P27 / PE11 / VCOM_RXWIFI_MOSI / P26
P25 / PE10 / VCOM_TXWIFI_MISO / P24
GNDGND
VRF
GND
VMCU
VCOM_EN / PE2 / P22
LED1 / PC1 / P20
LED0 / PC0 / P18
BUTTON1 / PA6 / P16
GND
BUTTON0 / PA2 / P14
I2C_SCL / PE1 / P12
VCOM_RTS / PE13 / P10
VCOM_CTS / PE12 / P8
PE15 / P6
PE14 / P4
PB12 / P2
PB11 / P0
VRF
J101 J102
Figure 4.2. Radio Board Pin Mapping on Breakout Pads
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4.2 Expansion Header
On the right hand side of the board an angled 20-pin expansion header is provided to allow connection of peripherals or plugin boards.
The connector contains a number of I/O pins that can be used with most of the WGM110 Wizard Gecko's features. Additionally, the
VMCU, 3V3 and 5V power rails are also exported.
The connector follows a standard which ensures that commonly used peripherals such as an SPI, a UART and an I2C bus are available
on fixed locations in the connector. The rest of the pins are used for general purpose IO. This allows the definition of expansion boards
that can plug into a number of different Silicon Labs starter kits.
The figure below shows the pin assignment of the expansion header for the Wi-Fi Module Wireless Starter Kit. Because of limitations in
the number of available GPIO pins, some of the expansion header pins are shared with kit features.
12
4
8
6
10
3
5
9
7
12
13
14
11
1516
17
18
20 19
VMCU
SPI_MOSI / PD0
SPI_MISO / PD1
SPI_SCK / PD2
SPI_CS / PD3
GPIO / PD4
GPIO / PD5
I2C_SDA / PE0
5V
3V3
GND
PB11 / GPIO
PB12 / GPIO
PE14 / GPIO
PE15 / GPIO
PE12 / (VCOM_CTS)
PE13 / (VCOM_RTS)
PE1 / I2C_SCL
Board ID SDA
Board ID SCL
Reserved (Board Identification)
WGM110 I/O Pin
Figure 4.3. Expansion Header
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4.2.1 Expansion Header Pin-out
Many pins on the WGM110 are shared between the Expansion Header and other functions on the Wireless STK Mainboard. Table
4.1 Expansion Header Pinout on page 6 includes an overview of the mainboard features that share pins with the Expansion Header.
Table 4.1. Expansion Header Pinout
Pin Connection EXP Header function Shared feature Peripheral mapping
20 3V3 Board controller supply
18 5V Board USB voltage
16 PE0 I2C_SDA SENSOR_I2C_SDA I2C1_SDA #2
14 PD5 GPIO
12 PD4 GPIO
10 PD3 SPI_CS USART1_CS #1
8 PD2 SPI_CLK SD_CLK / DISP_SCLK USART1_CLK #1
6 PD1 SPI_MISO SD_MISO USART1_RX #1
4 PD0 SPI_MOSI SD_MOSI / DISP_SI USART1_TX #1
2 VMCU WGM110 voltage domain, included in AEM measurements.
19 BOARD_ID_SDA Connected to Board Controller for identification of add-on boards.
17 BOARD_ID_SCL Connected to Board Controller for identification of add-on boards.
15 PE1 I2C_SCL SENSOR_I2C_SCL I2C1_SCL #2
13 PE13 GPIO VCOM_RTS
11 PE12 GPIO VCOM_CTS
9 PE15 GPIO
7 PE14 GPIO
5 PB12 GPIO
3 PB11 GPIO
1 GND Ground
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4.3 Debug Connector
The Debug Connector serves multiple purposes based on the "debug mode" setting which can be configured in Simplicity Studio. When
the debug mode is set to "Debug IN", the debug connector can be used to connect an external debugger to the WGM110 on the radio
board. When set to "Debug OUT", this connector allows the kit to be used as a debugger towards an external target. When set to "De-
bug MCU" (default), the connector is isolated from both the on-board debugger and the radio board target device.
Because this connector is electronically switched between the different operating modes, it can only be used when the Board Controller
is powered (i.e. J-Link USB cable connected). If debug access to the target device is required when the Board Controller is unpowered,
connect directly to the appropriate breakout pins.
The pinout of the connector follows that of the standard ARM Cortex Debug+ETM 19-pin connector. The pinout is described in detail
below. Even though the connector has support for both JTAG and ETM Trace, it does not necessarily mean that the kit or the on-board
target device supports this.
1 2
4
8
6
10
3
5
9
12
13 14
11
15 16
17 18
2019
TMS / SWDIO / C2D
TCK / SWCLK / C2CK
TDO / SWO
TDI / C2Dps
TRACECLK
TRACED0
TRACED1
TRACED2
TRACED3
RESET / C2CKps
GND
NC
NC
GND
GND
GND
7
GND
VTARGET
Cable Detect
NC
Figure 4.4. Debug Connector
Note: The pinout matches the pinout of an ARM Cortex Debug+ETM connector, but these are not fully compatible as pin 7 is physically
removed from the Cortex Debug+ETM connector. Some cables have a small plug that prevent them from being used when this pin is
present. If this is the case, remove the plug, or use a standard 2x10 1.27 mm straight cable instead.
Table 4.2. Debug Connector Pin Descriptions
Pin number(s) Function Description
1 VTARGET Target voltage on the debugged application.
2 TMS / SDWIO / C2D JTAG test mode select, Serial Wire data or C2 data
4 TCK / SWCLK / C2CK JTAG test clock, Serial Wire clock or C2 clock
6 TDO/SWO JTAG test data out or Serial Wire Output
8 TDI / C2Dps JTAG test data in, or C2D "pin sharing" function
10 RESET / C2CKps Target device reset, or C2CK "pin sharing" function
12 TRACECLK
14 TRACED0
16 TRACED1
18 TRACED2
20 TRACED3
9 Cable detect Connect to ground
11, 13 NC Not connected
3, 5, 15, 17, 19 GND Ground
Note: The Wireless STK Mainboard does not support this feature when used together with the Wizard Gecko WGM110 Module; howev-
er, BGTool can be used to debug BGAPI commands and error situations. For more information on BGTool go to Silicon Labs web page
http://www.silabs.com/start-wgm and download UG160: Wizard Gecko BGTool™ User's Guide.
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Connectors
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4.4 Simplicity Connector
The Simplicity Connector enables the advanced debugging features, such as the AEM, the Virtual COM port and the Packet Trace In-
terface, to be used towards an external target. The pinout is illustrated in the figure below.
VMCU 1
33V3
5
5V
15
GND
13
GND
11
GND
9
GND
7
GND
17
Board ID SCL
19
Board ID SDA
2Virtual COM TX / MOSI
4Virtual COM RX / MISO
6Virtual COM CTS / SCLK
8Virtual COM RTS / CS
10 Packet Trace 0 Sync
12 Packet Trace 0 Data
14 Packet Trace 0 Clock
16 Packet Trace 1 Sync
18 Packet Trace 1 Data
20 Packet Trace 1 Clock
Figure 4.5. Simplicity Connector
Note: Current drawn from the VMCU voltage pin is included in the AEM measurements, while the 3V3 and 5V voltage pins are not. To
monitor the current consumption of an external target with the AEM, unplug the Radio Board from the Wireless STK Mainboard to avoid
that the Radio Board current consumption is added to the measurements.
Table 4.3. Simplicity Connector Pin Descriptions
Pin number(s) Function Description
1 VMCU 3.3 V power rail, monitored by the AEM
3 3V3 3.3 V power rail
5 5V 5 V power rail
2 VCOM_TX_MOSI Virtual COM Tx/MOSI
4 VCOM_RX_MISO Virtual COM Rx/MISO
6 VCOM_CTS_SCLK Virtual COM CTS/SCLK
8 VCOM_RTS_CS Virtual COM RTS/CS
10 PTI0_SYNC Packet Trace 0 Sync
12 PTI0_DATA Packet Trace 0 Data
14 PTI0_CLK Packet Trace 0 Clock
16 PTI1_SYNC Packet Trace 1 Sync
18 PTI1_DATA Packet Trace 1 Data
20 PTI1_CLK Packet Trace 1 Clock
17 EXT_ID_SCL Board ID SCL
19 EXT_ID_SDA Board ID SDA
7, 9, 11, 13, 15 GND Ground
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5. Power Supply and Reset
5.1 Radio Board Power Selection
The WGM110 on a Wireless Starter Kit can be powered by one of these sources:
• the debug USB cable;
• a 3V coin cell battery; or
• a USB regulator on the Radio Board (for devices with USB support only).
The power source for the radio board is selected with the slide switch in the lower left corner of the Wireless STK Mainboard. shows
how the different power sources can be selected with the slide switch.
3.3V
VMCU
AEM
USB
BAT
USB Mini-B
Connector
Advanced
Energy
Monitor
5V
WGM110
BAT
USB
AEM
LDO
WSTK power select
slide switch
WGM110 Radio Board
USB Micro-B
Connector
DC/DC
Converter
Transistor
Switch
3.3V
USB 3.3V Enable
VBUS
CR2032
coin cell
(not supported for WGM110)
Figure 5.1. Power Switch
With the switch in the AEM position, a low noise 3.3 V LDO on the WSTK Mainboard is used to power the Radio Board. This LDO is
again powered from the debug USB cable. The Advanced Energy Monitor is now also connected in series, allowing accurate high
speed current measurements and energy debugging/profiling.
With the WGM110 radio board, the USB position of the power switch is disconnected. Instead, a transistor switch on the radio board
itself connects the on-board regulator to the module power supply when the target USB cable is inserted. Please note that this happens
regardless of the power switch position, so the power switch should be set to USB or BAT when using the radio board USB connector
to avoid conflict. The transistor switch allows the radio board to be powered by a USB cable even when removed from the WSTK main-
board.
With the switch in the BAT position, the WGM110 Module is powered by 2 x AA sized batteries. This requires that the external battery
holder with 2 x AA batteries is connected to the Expansion Header (after removing the Expansion Board).
The BAT switch position is the recommended position when powering the Radio Board with an external power source, as it disconnects
the internal LDO.
Note: The current sourcing capabilities of a coin cell battery is too low to supply normal operation of Wi-Fi based wireless applications.
Note: The Advanced Energy Monitor functionality is not supported when using the BRD4320A Radio Board with the Wireless STK
Mainboard.
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5.2 Board Controller Power
The board controller is responsible for important features such as the debugger and the Advanced Energy Monitor, and is powered
exclusively through the USB port in the top left corner of the board. This part of the kit resides on a separate power domain, so a differ-
ent power source can be selected for the target device while retaining debugging functionality. This power domain is also isolated to
prevent current leakage from the target power domain when power to the Board Controller is removed.
The board controller power domain is not influenced by the position of the power switch.
The kit has been carefully designed to keep the board controller and the target power domains isolated from each other as one of them
powers down. This ensures that the target WGM110 device will continue to operate in the USB and BAT modes.
5.3 WGM110 Reset
The WGM110 Wi-Fi Module can be reset by a few different sources:
• A user pressing the RESET button.
• The on-board debugger pulling the #RESET pin low.
• An external debugger pulling the #RESET pin low.
In addition to the reset sources mentioned above, a reset to the WGM110 will also be issued during Board Controller boot-up. This
means that removing power to the Board Controller (plugging out the J-Link USB cable) will not generate a reset, but plugging the cable
back in will, as the Board Controller boots up.
5.4 Battery Holder
In radio applications with high output power, peak current consumption will exceed the current sourcing capacity of a coin-cell battery.
To support evaluation of the WGM110 Wizard Gecko in situations where powering the kit from a wired USB connection is impractical,
for instance during range-tests, the kit is supplied with a battery holder for 2 AA batteries.
To use the battery holder, first set the power switch in the BAT position. Then attach the cable to pin 1 and 2 on the expansion header,
orienting the connector so the black cable cable goes down towards pin 1, and the red cable up towards pin 2.
Connect battery holder
to EXP header.
- Pin 2 (up): Red wire
- Pin 1 (down): Black wire
Put power switch in BAT position
Figure 5.2. Battery Holder Connection
Warning: There is no reverse voltage protection on the VMCU pin! Ensure that the battery holder is connected the right way. Failure to
do so may result in damage to the radio board and its components.
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6. Peripherals
The starter kit has a set of peripherals that showcase some of the features of the WGM110.
Be aware that most WGM110 I/O routed to peripherals are also routed to the breakout pads. This must be taken into consideration
when using the breakout pads for your application.
6.1 Push Buttons and LEDs
The kit has two user push buttons marked PB0 and PB1. They are connected directly to the WGM110, and are debounced by RC filters
with a time constant of 1 ms. The buttons are connected to pins PA2 and PA6.
The kit also features two yellow LEDs marked LED0 and LED1, that are controlled by GPIO pins on the WGM110. The LEDs are con-
nected to pins PC0 and PC1 in an active-high configuration.
PC1 (GPIO)
User Buttons
& LEDs
UIF_LED0
UIF_LED1
UIF_PB0
UIF_PB1
PA2 (GPIO)
PA6 (GPIO)
PC0 (GPIO)
WGM110
Figure 6.1. Buttons and LEDs
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6.2 Memory LCD-TFT Display
A 1.28-inch SHARP Memory LCD-TFT is available on the kit to enable interactive applications to be developed. The display has a high
resolution of 128 by 128 pixels, and consumes very little power. It is a reflective monochrome display, so each pixel can only be light or
dark, and no backlight is needed in normal daylight conditions. Data sent to the display is stored in the pixels on the glass, which means
no continous refreshing is required to maintain a static image.
The display interface consists of an SPI-compatible serial interface and some extra control signals. Pixels are not individually addressa-
ble, instead data is sent to the display one line (128 bits) at a time.
The Memory LCD-TFT display is shared with the kit Board Controller, allowing the Board Controller application to display useful infor-
mation when the user application is not using the display. The user application always controls ownership of the display with the
DISP_ENABLE signal:
• DISP_ENABLE = LOW: The Board Controller has control of the display
• DISP_ENABLE = HIGH: The user application (WGM110) has control of the display
Power to the display is sourced from the target application power domain when the WGM110 controls the display, and from the Board
Controller's power domain when the DISP_ENABLE line is low. Data is clocked in on DISP_SI when DISP_CS is high, and the clock is
sent on DISP_SCLK. The maximum supported clock speed is 1.1 MHz.
DISP_COM is the "COM Inversion" line. It must be pulsed periodically to prevent static build-up in the display itself. Please refer to the
display application information for details on driving the display:
http://www.sharpmemorylcd.com/1-28-inch-memory-lcd.html
PD2 (USART1_CLK)
PD0 (USART1_TX)
PC14 (GPIO)
PC15 (GPIO)
PC13 (GPIO)
WGM110
0: Board Controller controls display
1: WGM110 controls display
Figure 6.2. 128x128 Pixel Memory LCD
Note: The WGM110 Module Wi-Fi Software stack does not include a driver for the Memory LCD.
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6.3 Si7021 Relative Humidity and Temperature Sensor
The Si7021 I2C relative humidity and temperature sensor is a monolithic CMOS IC integrating humidity and temperature sensor ele-
ments, an analog-to-digital converter, signal processing, calibration data, and an I2C Interface. The patented use of industry-standard,
low-K polymeric dielectrics for sensing humidity enables the construction of low-power, monolithic CMOS Sensor ICs with low drift and
hysteresis, and excellent long term stability.
The humidity and temperature sensors are factory-calibrated and the calibration data is stored in the on-chip non-volatile memory. This
ensures that the sensors are fully interchangeable, with no recalibration or software changes required.
The Si7021 is available in a 3x3 mm DFN package and is reflow solderable. It can be used as a hardware- and software-compatible
drop-in upgrade for existing RH/ temperature sensors in 3x3 mm DFN-6 packages, featuring precision sensing over a wider range and
lower power consumption. The optional factory-installed cover offers a low profile, convenient means of protecting the sensor during
assembly (e.g., reflow soldering) and throughout the life of the product, excluding liquids (hydrophobic/oleophobic) and particulates.
The Si7021 offers an accurate, low-power, factory-calibrated digital solution ideal for measuring humidity, dew-point, and temperature,
in applications ranging from HVAC/R and asset tracking to industrial and consumer platforms.
The I2C bus used for the Si7021 is shared with the Expansion Header. The temperature sensor is normally isolated from the I2C line. To
use the sensor, SENSOR_ENABLE (PC9) must be set high. When enabled, the sensor's current consumption is included in the AEM
measurements.
SENSOR_ENABLE
0: I2C lines are isolated, sensor is not powered
1: Sensor is powered and connected
PE1 (I2C1_SCL)
PE0 (I2C1_SDA)
PC9 (GPIO)
SENSOR_I2C_SDA
SENSOR_I2C_SCL
VMCU
VDD
SCL
SDA Temperature
& Humidity
Sensor
WGM110
Si7021
Figure 6.3. Si7021 Relative Humidity and Temperature Sensor
Please refer to the Silicon Labs web pages for more information: http://www.silabs.com/humidity-sensors
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6.4 USB Micro-B Connector
The BRD4320A radio board is equipped with a USB Micro-B connector that is connected directly to the WGM110 Wizard Gecko. Figure
6.4 Radio Board USB Connector on page 14 shows how the USB lines are connected to the WGM110.
This USB connector may also be used to power the Radio Board. This is allows the Radio Board to be powered externally while the
Wireless STK Mainboard can be switched completely off.
The radio board contains a voltage regulator and a transisor switch that automatically connects the regulated supply to the module pow-
er supply. The power select slide switch on the Wireless STK Mainboard should be set to USB or BAT to avoid conflict with the Main-
board power supply when using the USB connector.
Note: Software configuration details for using the USB connector of the Radio Board are described in the "UG161: WGM110 Wi-Fi
Module Configuration User's Guide".
USB micro B
Connector
VBUS
D+
D-
USB Micro-B
Connector
USB_DM (PF10)
USB_DP (PF11)
USB_VBUS
USB_VREGI
USB_VREGO
1 uF 4.7 uF
WGM110
Figure 6.4. Radio Board USB Connector
6.5 MicroSD Card Slot
BRD4320A contains a microSD card slot which is connected to the Wizard Gecko WGM110 Wi-Fi Module. It enables testing of SW
applications utilizing a microSD or microSDHC card. The memory card can be accessed from the host processor using BGAPI com-
mands, BGScript commands or by using the internal HTTP Server of the Module.
Note: The microSD card slot is located on the bottom side of the BRD4320A Radio Board. To install a microSD or microSDHC card
remove the Radio Board from the WSTK Mainboard and push the microSD or microSDHC card into the card slot with the metal con-
tacts of the memory card facing towards the PCB and attach the Radio Board back into WSTK Mainboard connectors.
CHARACTERISTICS
Supported file systems: FAT 16 and FAT 32
Maximum memory size: 32 GB.
Supported memory card types: microSD and microSDHC.
Programming related information
The microSD card slot is connected to USART1 Location 1 of the WGM110 Module and the Chip Select to Port D Bit 7.
GPIO pinout, interfaces and alternative locations are described in the WGM110 Wi-Fi Module Data Sheet, hardware configuration in the
UG161: WGM110 Wi-Fi Module Configuration User's Guide and related commands in detail in the WGM110 API Reference Manual.
The connection between the microSD card slot and the WGM110 Module are shown below:
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CMD_MOSI
DAT0_MISO
CLK
CD_DAT3_CS
DETECT
WGM110
microSD Card
Connector
PD0 (USART1_TX)
PD1 (USART1_RX)
PD2 (USART1_CLK)
PD7 (GPIO)
PD6 (GPIO)
Figure 6.5. Connection between Radio Board microSD Card Slot and WGM110 Module
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6.6 Virtual COM Port
An asynchronous serial connection to the board controller is provided for application data transfer between a host PC and the target
WGM110. This eliminates the need for an external serial port adapter.
VCOM_ENABLE
PE10 (US0_TX#0)
PE11 (US0_RX#0)
PE2 (GPIO)
VCOM_RX
VCOM_TX
Board
Controller
WGM110
USB Host
PC
Isolation & Level Shift
PE12 (GPIO)
PE13 (GPIO)
VCOM_CTS
VCOM_RTS
ETH
or
Figure 6.6. Virtual COM Port Interface
The Virtual COM port consists of a physical UART between the target device and the board controller, and a logical function in the
board controller that makes the serial port available to the host PC over USB or Ethernet. The UART interface consists of four pins and
an enable signal.
Table 6.1. Virtual COM Port Interface Pins
Signal Description
VCOM_TX Transmit data from the WGM110 to the board controller
VCOM_RX Receive data from the board controller to the WGM110
VCOM_CTS Clear to Send hardware flow control input, asserted by the board controller when it is ready to receive more data
VCOM_RTS Request to Send hardware flow control output, asserted by the WGM110 when it is ready to receive more data
VCOM_ENABLE Enables the VCOM interface, allowing data to pass through to the board controller.
The parameters of the serial port, such as baud rate or flow control, can be configured using the admin console. The default settings
depends on which radio board is used with the Wireless STK Mainboard. Please see for more details.
Note: The VCOM port is only available when the board controller is powered, which requires the J-Link USB cable to be inserted.
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7. Expansion Board
The User Interface Expansion Board included with the WGM110 Wireless STK includes the following features:
• 1x 3-axis accelerometer (Bosch Sensortech BMA280)
• 1x Joystick with 9 measurable positions
• 2x Push buttons and 2x LEDs
The connections between the Expansion Board and the WGM110 are shown in the figure below:
PD5 (GPIO)
BUTTON_LED2 (EXP7)
PE14 (GPIO)
WGM110
BUTTON_LED3 (EXP14) Buttons
& LEDs
Accelerometer
BMA280
Analog
Joystick
JOYSTICK (EXP12)
ACC_MOSI (EXP4)
ACC_MISO (EXP6)
ACC_SCK (EXP8)
ACC_CS (EXP10)
ACC_INT (EXP9)
PD4 (ADC0_CH4)
PD0 (USART1_TX)
PD1 (USART1_RX)
PD2 (USART1_CLK)
PD3 (USART1_CS)
PE15 (GPIO)
Figure 7.1. User Interface Expansion Board
The following sections contain more detailed information about each feature.
7.1 Accelerometer
Bosch Sensortec BMA280 is a triaxial, low-power, low-g accelerometer sensor with SPI interface. It features 14-bit digital resolution and
allows very low-noise measurement of acceleration in 3 perpendicular axes and can therefore sense tilt, motion, shock and vibration.
Please refer to Bosch Sensortec's product page for a detailed datasheet of this sensor: http://www.bosch-sensortec.com/bst/products/
all_products/bma280
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7.2 Push Buttons and LEDs
The Expansion Board contains two push buttons (marked BTN2 and BTN3 on the PCB) and two LEDs (LED2 and LED3, not marked
but placed correspondingly above the push button markings). One push button and one LED share the same I/O pin on the WGM110.
The push button is connected to the LED through a transistor, allowing the I/O to be used either as an input (for reading the push button
state) or as an output (to control the LED state on or off).
When configured as an input, "0" indicates that the button is being pressed and "1" that the push button is not being pressed. Likewise,
when configured as an output, "0" will turn the LED on and "1" will turn it off.
Pressing a push button will also light up the corresponding LED because the LED is controlled by the same line (state) regardless of
whether it is the WGM110 or the push button that pulls the line low.
The each button is debounced by an RC filter with a time constant of about 1 ms. Pressing the push button while having the pin config-
ured as an output in high state ("1") will not cause damage, but will cause extra current to flow.
7.3 Joystick
The analog joystick offers 9 measureable positions. This joystick is connected to the WGM110 pin PD4. Each of the joystick output pins
are connected to a different resistor value to create a unique voltage that is measured by the internal ADC on the WGM110. The joy-
stick output is connected to AD Channel 0 (ADC0). The figure below shows the connection between the joystíck and the WGM110.
ADC0 CH4
WGM110
ADC0 CH4_miso
MX25R8035F
8 Mbit
Figure 7.2. User Interface Expansion Board Joystick
The table below lists the expected output voltage from each joystick position.
Table 7.1. Joystick Output Voltage
Position Resistor combinations [kohm] Joystick output voltage [V]1
Center press 0.1 / (0.1 + 10) 0.03 V
Up (N) 60.4 / (60.4 + 10) 2.83 V
Up-Right (NE) {(N // E) / {(N // E) + 10 } = 21.34 / (21.34
+ 10)
2.25 V
Right (E) 33 / (33 + 10) 2.53 V
Down-Right (SE) (S // E) / {(S // E) + 10)} = 7.67 / (7.67 + 10) 1.43 V
Down (S) 10 / (10 + 10) 1.65 V
Down-Left (SW) (S // W) / {(S // W) + 10)} = 6 / (6 + 10) 1.24 V
Left (W) 15 / (15 + 10) 1.98 V
Up-Left (NW) (N // W) / {(N // W) + 10)} = 12.01 / (12.01
+ 10)
1.80 V
Note: 1) Output Voltage is calculated with VMCU of 3.3 V .
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8. Board Controller
The Wireless STK Mainboard contains a microcontroller separate from the WGM110 Wizard Gecko that is responsible for some of the
advanced kit features provided. This microcontroller is referred to as the "Board Controller", and is not programmable by the user. The
board controller acts as an interface between the host PC and the target device on the radio board, as well as handling some house-
keeping functions on the board.
Some of the kit features actively managed by the board controller are:
• The On-board Debugger, which can flash and debug both on-board and external targets.
• The , which provides real-time energy profiling of the user application.
• The Packet Trace Interface , which is used in conjunction with PC software to provide detailed insight into an active radio network.
• The and interfaces, which provide ways to transfer application data between the host PC and the target processor.
• The Admin Console, which provides configuration of the various board features.
Silicon Labs publishes updates to the board controller firmware in form of firmware upgrade packages. These updates may enable new
features or fix issues. See 10.2 Firmware Upgrades for details on firmware upgrade.
8.1 Admin Console
The admin console is a command line interface to the board controller on the kit. It provides functionality for configuring the kit behavior
and retreiving configuration and operational parameters.
■Connecting
The Wireless STK Mainboard must be connected to Ethernet using the Ethernet connector in the top left corner of the mainboard for
the admin console to be available. See ● Ethernet Interface for details on the Ethernet connectivity.
Connect to the Admin Console by opening a telnet connection to the kit's IP address, port number 4902.
When successfully connected, a WSTK> prompt is displayed.
■Built-in Help
The admin console has a built in help system which is accessed by the help command. The help command will print a list of all top
level commands:
WSTK> help
*************** Root commands ****************
aem AEM commands [ calibrate, current, dump, ... ]
boardid Commands for board ID probe. [ list, probe ]
dbg Debug interface status and control [ info, mode,]
dch Datachannel control and info commands [ info ]
discovery Discovery service commands.
net Network commands. [ dnslookup, geoprobe, ip ]
pti Packet trace interface status and control [ config, disable, dump, ... ]
quit Exit from shell
sys System commands [ nickname, reset, scratch, ... ]
target Target commands. [ button, flashwrite, go, ... ]
time Time Service commands [ client, server ]
user User management functions [ login,]
The help command can be used in conjunction with any top level command to get a list of sub-commands with description. For exam-
ple, pti help will print a list of all available sub-commands of pti:
WSTK> pti help
*************** pti commands ****************
config Configure packet trace
disable Disable packet trace
dump Dump PTI packets to the console as they come
enable Enable packet trace
info Packet trace state information
This means that running pti enable will enable packet trace.
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