Midatronics SHARKY I User manual

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SHARKY - User’s Guide 2020/11/18
Doc: UG_MDX-STWBx, Rev 1.7
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SHARKY I & II
User’s Guide
MDX-STWBP-R01 : Sharky PCB Ant.
MDX-STWBU-R01 : Sharky uFL antenna
All information contained in these materials, including products and product specifications,
represents information on the product at the time of publication and is subject to change
by Midatronics S.r.l. without notice.

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Outline
1. FCC Rules 5
1.1. List of FCC rules 5
2. Introduction 5
2.1. Description 5
3. System Overview 7
3.1. BLE Technology Overview 7
3.2. BLE Mesh Technology overview 9
3.3. Thread Technology overview 10
3.4. STM32WB Wireless System-on-Chip 12
3.5. Block Diagram 14
4. Connectors 15
4.1. Sharky Module 16
5. Usage 20
5.1. Power Supply 20
5.2. Sharky Connections 21
5.2.1. Power Supply on module configuration 21
5.2.2. Power Supply 22
5.2.3. Reset Circuit 22
5.2.4. Boot0 pin 23
5.2.5. SWD - JLink-V3SET connection 24
5.3. STLink-V3SET expansion board 25
5.4. Operating Conditions 26
6. Board Layout 27
6.1. Sharky Module 27
6.2. Mounting Suggestions 28
6.2.1. Sharky PCB Antenna 29
6.2.2. Sharky uFL Antenna 30
6.2.3. Sharky uFL Suggested Antennas 30

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6.3. Sharky Breakout 31
6.3.1. Sharky PCB/uFL antenna 31
7. Radiation pattern plots 32
7.1. Sharky PCB-Ant module 32
8. Firmware Upload 33
8.1. FW upload to M4 core 33
8.2. FW upload to M0+ core 33
9. Software Development 35
10. References and Useful Links 36
10.1. Data Sheets and documents 36
10.2. Tools 36
10.3. WebSites 36
10.4. Bibliography 36
11. FCC 37
11.1. Label and Compliance Information (FCC) 37

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Revisions
REVISION DATE DESCRIPTION STATUS
A
UTHOR REVISER
1.0 2019/04/04 First Release Draf
t
info
@
midatronics.com U
A
-EM
1.1 2019/09/19 Chan
g
ed chap 9 Draf
t
info
@
midatronics.com U
A
-EM
1.2 2020/02/07 Changed chap
3.1, 4, 5, 6
Draft [email protected] UA-EM
1.3 2020/03/30
A
dded chap 4.4 Draf
t
info
@
midatronics.com U
A
1.4 2020/05/29 Chan
g
es for FCC Draf
t
info
@
midatronics.com U
A
1.5 2020/06/11 Updated Sharky
Dimension ima
g
e
Draft [email protected] UA
1.6 2020/07/20 Updated chap.
4.1
Draft [email protected] UA
1.7 2020/11/18 Changes for FCC Final [email protected] AC
Disclaimer
All rights strictly reserved. Reproduction in any form is not permitted without
written authorization from Midatronics S.r.l.
Midatronics S.r.l.
Via Zucchi 1 20900
Monza (Monza Brianza)
Italy
[email protected]
www.midatronics.com

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1. FCC Rules
1.1. List of FCC rules
The SHARKY module have received Federal Communications Commission (FCC) CFR47
Telecommunications, Part 15 Subpart C “Intentional Radiators” single-modular approval in
accordance with Part 15.212 Modular Transmitter approval.
According to FCC Part 15.212 the single-modular transmitter is a completely self-contained
radiofrequency transmitter device that is typically incorporated into another product, host or
device and complies to all the conditions to be defined as a “single modular transmitter”.
The Midatronics SHARKY Modular Transmitter is also compliant to FCC Part 15.247 insofar
as it is a device using a wide band modulation inside the band 2400-2483.5 MHz with a 6dB
bandwidth greater than 500kHz.
2. Introduction
2.1. Description
This document describes the Sharky modules.
Sharky is a complete family of modules that enables customer to test and integrate the new
STM32WB MCU for rapid prototyping and fast time to market.
Sharky modules are based on STMicroelectronics STM32WB55CE, a dual-core MCUs with
wireless support based on an Arm® Cortex®-M4 core running at 64 MHz (application
processor) plus an Arm® Cortex®-M0+ core at 32 MHz (network processor).
With two totally independent cores, this innovative architecture is optimized for real-time
execution (radio-related software processing).
The STM32WB55 Bluetooth 5.0-certified device offers Mesh 1.0 software support, multiple
profiles and flexibility to integrate proprietary BLE stacks.
OpenThread-certified software stack is available. The radio can also run BLE/OpenThread
protocols concurrently. The embedded generic MAC allows the usage of other IEEE 802.15.4
proprietary stacks like ZigBee®, or proprietary protocols, giving even more options for
connecting devices to the Internet of Things (IoT).
The Sharky module is available in four versions:
●Sharky with PCB Antenna
●Sharky with uFL connector
Sharky modules are sold standalone or soldered on a breakout board for easy connections.

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Main features
●Module size 16.1 x 27.3 mm
●Module with:
○PCB antenna
○uFL antenna connector
●Integrated BLE/OpenThread or IEEE 802.15.4 programmable networking stacks

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3. System Overview
3.1. BLE Technology Overview
Bluetooth Low Energy (BLE) is the main feature of the Bluetooth specification v4.0 released
in December 2009. BLE is a new protocol that allows for long-term operation of Bluetooth
devices that transmit low volumes of data. BLE enables smaller form factors, better power
optimization, and the ability to operate on a small power cell for several years.
The classic Bluetooth specification defines a uniform structure for a wide range of devices that
connect to each other. Bluetooth operates primarily using ad hoc piconets. A master device
controls up to seven slaves per piconet; the slaves communicate with the master device but
they do not communicate with each other. However, a slave device may participate in one or
more piconets, essentially a collection of devices connected via Bluetooth. A summary of
classic Bluetooth topology with multiple piconets, called scatternet, can be found below.
Figure 1. Bluetooth Scatternet topology
In a BLE topology, the slaves each communicate on a separate physical channel with the
master. Unlike a classic Bluetooth piconet, where all slaves listen for incoming connections
and therefore need to be on constant standby, a BLE slave invites connections and so is in
total control of when to consume power. A BLE master, which is assumed to have less power
constraints, will listen for advertisements and make connections on the back of an
advertisement packet. A diagram of this can be found below.

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Figure 2. BLE Sta
r
-bus Topology
While BLE inherits the operating spectrum and the basic structure of the communication
protocol from the classic Bluetooth protocol, BLE implements a new lightweight Link Layer
that provides ultra-low power idle mode operation, fast device discovery, and reliable and
secure point-to-multipoint data transfers. As a result, BLE offers substantially lower peak,
average, and idle-mode power consumption than classic Bluetooth. Averaged over time, BLE
consumes only 10% of the power consumed by classic Bluetooth.
In addition to its ultra-low power consumption, BLE has several unique features that set it apart
from other available wireless technologies, including:
●Interoperability: Like classic Bluetooth devices, BLE devices follow standards set by
the Bluetooth Special Interest Group (SIG), and BLE devices from different
manufacturers interoperate.
●Robustness: BLE uses fast frequency hopping to secure a robust transmission even
in the presence of other wireless technologies.
●Ease of Use: BLE has been developed so that it is straightforward for designers to
implement it in a variety of different applications.
●Latency: The total time to send small chunks of data is generally fewer than 6 ms, and
as low as 3 ms (compared to 100 ms with classic Bluetooth).
●Range: Thanks to an increased modulation index, BLE technology offers greater range
(up to 200 feet and beyond, in ideal environments) than to classic Bluetooth offers.

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3.2. BLE Mesh Technology overview
Figure 3. BLE Mesh Topology
Borrowing from the original Bluetooth specification, the Bluetooth SIG defines several profiles
— specifications for how a device works in a particular application — for low energy devices.
Manufacturers are expected to implement the appropriate specifications for their device in
order to ensure compatibility. A device may contain implementations of multiple profiles.
Majority of current low energy application profiles is based on the generic attribute profile
(GATT), a general specification for sending and receiving short pieces of data known as
attributes over a low energy link. Bluetooth mesh profile is the exception to this rule as it is
based on General Access Profile (GAP).
Bluetooth mesh profiles use Bluetooth Low Energy to communicate with other Bluetooth Low
Energy devices in the network. Each device can pass the information forward to other
Bluetooth Low Energy devices creating a "mesh" effect. For example, switching off an entire
building of lights from a single smartphone.
Conceptually, the Bluetooth Mesh Standard is defined as a publish/subscribe model where
publishers can publish to a certain topic and subscribers can subscribe to one or more topics
of interest.
This concept is used as an inspiration for the implementation in the standard. A node in a
Bluetooth Mesh network can subscribe to one or more addresses (stored in the subscriber
list) and publish to one specific address (stored in the publish address).

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To be able to connect these different publishers and subscribers, a mesh topology is created.
The standard uses BLE advertising and scanning as an underlying technology to implement
communication. To communicate in a Bluetooth Mesh network, a flooding mechanism is used.
By default, a flooding mechanism ensures that each node in the network repeats incoming
messages, so that they are relayed further, until the destination node is reached.
The standard uses a new type of BLE advertisement packet to communicate in a mesh
network, which is only supported by devices that support both BLE and Bluetooth Mesh.
Fortunately, the standard also defines a backwards compatibility feature to ensure that BLE
devices which do not support Bluetooth Mesh can also be part of a Bluetooth Mesh network.
3.3. Thread Technology overview
Thread is a secure, wireless mesh networking protocol. The Thread stack is an open
standard that is built upon a collection of existing Institute for Electrical and Electronics
Engineers (IEEE) and Internet Engineering Task Force (IETF) standards.
The Thread stack supports IPv6 addresses and provides low-cost bridging to other IP
networks and is optimized for low-power/battery-backed operation, and wireless device-
to-device communication. The Thread stack is designed specifically for Connected Home
applications where IP-based networking is desired and a variety of application layers can
be used on the stack.
Figure 4. Thread Network Architecture
These are the general characteristics of the Thread stack focused on the Connected
Home:
● Simple network installation, start-up, and operation: The Thread stack
supports several network topologies. Installation is simple using a smartphone,

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tablet, or computer. Product installation codes are used to ensure only authorized
devices can join the network. The simple protocols for forming and joining networks
allow systems to self-configure and fix routing problems as they occur.
●
Secure: Devices do not join the network unless authorized and all communications
are encrypted and secure. Security is provided at the network layer and can be at
the application layer. All Thread networks are encrypted using a smartphone-era
authenticationscheme and Advanced Encryption Standard (AES) encryption. The
security used in Thread networks is stronger than other wireless standards the
Thread Group has evaluated.
●
Small and large networks: Home networks vary from several to hundreds of
devices. The networking layer is designed to optimize the network operation based
on the expected use.
●
Range: Typical devices provide sufficient range to cover a normal home. Readily
available designs with power amplifiers extend the range substantially. A
distributed spread spectrum is used at the Physical Layer (PHY) to be more
immune to interference.
●
No single point of failure: The Thread stack is designed to provide secure and
reliable operations even with the failure or loss of individual devices.
●
Low power: Devices efficiently communicate to deliver an enhanced user
experience with years of expected life under normal battery conditions. Devices
can typically operate for several years on AA type batteries using suitable duty
cycles.
●
Cost-effective: Compatible chipsets and software stacks from multiple vendors
are priced for mass deployment, and designed from the ground up to have
extremely low-power consumption. Typical home products run in the connected
home include: normally powered (lighting, appliances, HVAC, fans), powered or
battery-operated (thermostats, smoke detectors, CO and CO2detectors, security
systems), and normally battery-operated (door sensors, window sensors, motion
sensors, door locks).

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3.4. STM32WB Wireless System-on-Chip
The Sharky modules are based on STMicroelectronics STM32WB55CE, a dual-core MCUs
with wireless support are based on an Arm® Cortex®-M4 core running at 64 MHz (application
processor) plus an Arm® Cortex®-M0+ core at 32 MHz (network processor).
The STM32WB platform is an evolution of the well-known market-leading STM32L4
ultra-low-power series of MCUs. It provides the same digital and analog peripherals suitable
for applications requiring extended battery life and complex functionalities.
STM32WB proposes a variety of communication assets, a practical crystal-less USB2.0 FS
interface, audio support, an LCD driver, up to 72 GPIOs, an integrated SMPS for power
consumption optimization, and multiple low-power modes to maximize battery life.
On top of wireless and ultra-low-power aspects, a particular focus was placed on embedding
security hardware functions such as a 256-bit AES, PCROP, JTAG Fuse, PKA (elliptic curve
encryption engine), and Root Secure Services (RSS). The RSS allows authenticating OTA
communications, regardless of the radio stack or application.
For more informations on STM32WB visit the following site:
https://www.st.com/en/microcontrollers/stm32wb-
series.html?querycriteria=productId=SS1961

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Figure 5. STM32WB55CE pinout

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3.5. Block Diagram
Figure 6. Sharky Module with PCB Antenna / or uFL connector
ARM
Cortex
M4
Application
512
KByte
Flash
ARM
Cortex
M0+
Networking
Stack
256
KByte
SRAM
IPCC
USART SPI I2C USB DIO
STM32WB55CE
ADC LCD
RF
Front
End
32
MHz
32.7
KHz
DC/DC
PCB Antenna
or uFL
connector
AES2
56

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4. Connectors
The following picture shows the connectors of the three Sharky types. The following MCU pins
are used internally and not exposed in connector:
PIN NAME/FUNCTION Connected to:
2 PC14-OSC32_IN 32.768 KHzquartz oscillato
r
3 PC15-OSC32_OUT 32.768 KHz quartz oscillato
r
25 OSC_IN 32 MHz quartz oscillato
r
24 OSC_OUT 32 MHz quartz oscillato
r
21 RF1 2.4 GHz Filte
r
26
A
T0 n.c.
27
A
T1 n.c.
34 VDDSMPS VCC
33 VLXSMPS SMPS circuit
31 VFBSMPS SMPS circuit
32 VSSSMPS SMPS circuit
23 VDDRF Filter Capacitors
22 VSSRF Filter Capacitors
EP EP GND
Table 1. Module internal pins

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4.1. Sharky Module
Figure 8. Sharky Module pinout

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Sharky
Pin
pin SoC Pin typ str STM32WB55CE I/O
P1 GND S
P2 28 PB0 I/O TT COMP1_OUT, CM4_EVENTOUT, EXT_PA_TX
P3 29 PB1 I/O TT LPUART1_RTS_DE, LPTIM2_IN1, CM4_EVENTOUT
P4 30 PE4 I/O FT CM4_EVENTOUT
P5 GND S
P6 47 PB7 I/O FT_fla LPTIM1_IN2, TIM1_BKIN, I2C1_SDA, USART1_RX,
TSC_G2_IO4, LCD_SEG21, TIM17_CH1N,
CM4_EVENTOUT, COMP2_INM, PVD_IN
P7 41 PA14 I/O FT_l JTCK-SWCLK, LPTIM1_OUT, I2C1_SMBA,
LCD_SEG5, SAI1_FS_B, CM4_EVENTOUT
P8 36 PA10 I/O FT_fl TIM1_CH3, SAI1_PDM_DI1, I2C1_SDA, USART1_RX,
USB_CRS_SYNC, LCD_COM2, SAI1_SD_A,
TIM17_BKIN, CM4_EVENTOUT
P9 42 PA15 I/O FT_l JTDI, TIM2_CH1, TIM2_ETR, SPI1_NSS,
TSC_G3_IO1, LCD_SEG17, CM4_EVENTOUT
P10 39 PA13 I/O FT_u JTMS-SWDIO, IR_OUT, USB_NOE, SAI1_SD_B,
CM4_EVENTOUT
P11 37 PA11 I/O FT_u TIM1_CH4, TIM1_BKIN2, SPI1_MISO, USART1_CTS,
USB_DM, CM4_EVENTOUT
P12 38 PA12 I/O FT_u TIM1_ETR, SPI1_MOSI, LPUART1_RX,
USART1_RTS_DE, USB_DP, CM4_EVENTOUT
P13 43 PB3 I/O FT_la JTDO-TRACESWO, TIM2_CH2, SPI1_SCK,
USART1_RTS_DE, LCD_SEG7, SAI1_SCK_B,
CM4_EVENTOUT, COMP2_INM
P14 GND S
P15 44 PB4 I/O FT_fla NJTRST, I2C3_SDA, SPI1_MISO,
USART1_CTS,TSC_G2_IO1, LCD_SEG8,
SAI1_MCLK_B, TIM17_BKIN, CM4_EVENTOUT,
COMP2_INP
P16 45 PB5 I/O FT_l LPTIM1_IN1, I2C1_SMBA, SPI1_MOSI, USART1_CK,
LPUART1_TX, TSC_G2_IO2, LCD_SEG9,
COMP2_OUT, SAI1_SD_B, TIM16_BKIN,
CM4_EVENTOUT
P17 46 PB6 I/O FT_fla LPTIM1_ETR, I2C1_SCL, USART1_TX, TSC_G2_IO3,
LCD_SEG6, SAI1_FS_B, TIM16_CH1N, MCO,
CM4_EVENTOUT, COMP2_INP
P18 40 VDDUSB S

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P19 VCC S
P20 4 PH3 I/O FT BOOT0, CM4_EVENTOUT, LSCO
P21 GND S
P22 1 VBAT S
P23 5 PB8 I/O FT_fl TIM1_CH2N, SAI1_PDM_CK1, I2C1_SCL,
QUADSPI_BK1_IO1, LCD_SEG16, SAI1_MCLK_A,
TIM16_CH1, CM4_EVENTOUT
P24 8 VDD
A
S
P25 6 PB9 I/O FT_fla TIM1_CH3N, SAI1_PDM_DI2,
I2C1_SDA, SPI2_NSS, IR_OUT, TSC_G7_IO4,
QUADSPI_BK1_IO0, LCD_COM3, SAI1_FS_A,
TIM17_CH1, CM4_EVENTOUT
P26 GND S
P27 9 PA0 I/O FT_a TIM2_CH1, COMP1_OUT, SAI1_EXTCLK, TIM2_ETR,
CM4_EVENTOUT, COMP1_INM, ADC1_IN5,
RTC_TAMP2/WKUP1
P28 10 PA1 I/O FT_la TIM2_CH2, I2C1_SMBA, SPI1_SCK, LCD_SEG0,
CM4_EVENTOUT, COMP1_INP, ADC1_IN6
P29 11 PA2 I/O FT_la LSCO, TIM2_CH3, LPUART1_TX,
QUADSPI_BK1_NCS, LCD_SEG1, COMP2_OUT,
CM4_EVENTOUT, COMP2_INM, ADC1_IN7,
WKUP4/LSCO
P30 7 NRST I/O RST
P31 12 PA3 I/O FT_la TIM2_CH4, SAI1_PDM_CK1, LPUART1_RX,
QUADSPI_CLK, LCD_SEG2, SAI1_MCLK_A,
CM4_EVENTOUT, COMP2_INP, ADC1_IN8
P32 13 PA4 I/O FT_a SPI1_NSS, SAI1_FS_B, LPTIM2_OUT, LCD_SEG5,
CM4_EVENTOUT, COMP1_INM, COMP2_INM,
A
DC1_IN9
P33 14 PA5 I/O FT_a TIM2_CH1, TIM2_ETR, COMP1_INM, COMP2_INM,
SPI1_SCK, LPTIM2_ETR, ADC1_IN10, SAI1_SD_B,
CM4_EVENTOUT
P34 15 PA6 I/O FT_la TIM1_BKIN, SPI1_MISO, LPUART1_CTS,
QUADSPI_BK1_IO3, LCD_SEG3, TIM16_CH1,
CM4_EVENTOUT, ADC1_IN11
P35 16 PA7 I/O FT_fla TIM1_CH1N, I2C3_SCL, SPI1_MOSI,
QUADSPI_BK1_IO2, ADC1_IN12, LCD_SEG4,
COMP2_OUT, TIM17_CH1, CM4_EVENTOUT
P36 17 PA8 I/O FT_la MCO, TIM1_CH1, SAI1_PDM_CK2, USART1_CK,
LCD_COM0, SAI1_SCK_A, LPTIM2_OUT,

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CM4_EVENTOUT, ADC1_IN15
P37 18 PA9 I/O FT_fla TIM1_CH2, SAI1_PDM_DI2, I2C1_SCL, SPI2_SCK,
COMP1_INM, ADC1_IN16, USART1_TX, LCD_COM1,
SAI1_FS_A, CM4_EVENTOUT
P38 19 PB2 I/O FT_a RTC_OUT, LPTIM1_OUT, I2C3_SMBA, SPI1_NSS,
LCD_VLCD, SAI1_EXTCLK, CM4_EVENTOUT,
COMP1_INP
P39 GND S
P40 GND S
Table 2. Sharky Pinout
Legend:
Name
A
bbreviation Definition
typ
S Supply Pin
I Input only pin
I/O Input / output pin
str
FT 5 V tolerant I/O
TT 3.6 V tolerant I/O
RF RF I/O
RST Bidirectional reset pin with weak pull-up resistor
Option for TT or FT I/Os
_f I/O, Fm+ capable
_I I/O, with LCD function supplied by V LCD
_u I/O, with USB function supplied by V DDUSB
_a I/O, with Analog switch function supplied by V DDA
Notes Unless specified, all I/Os are set as analog inputs during and after reset.

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5. Usage
This chapter describes how to connect, configure and interact with the Sharky and Sharky Pro
modules.
5.1. Power Supply
Sharky and Sharky PRO modules are powered by:
●VCC/VDD pins, from 1.71 V to 3.6 V
●VDDA pin, from 1.62 V (ADCs/COMPs) to 2.4 V (VREFBUF) to 3.6 V .
VDDA is the external analog power supply for A/D converters, D/A converters, voltage
reference buffer, operational amplifiers and comparators. The VDDA voltage level is
independent from the VDD voltage and should preferably be connected to VDD when
these peripherals are not used.
●VDDUSB = 3.0 V to 3.6 V
VDDUSB is the external independent power supply for USB transceivers. The
VDDUSB voltage level is independent from the VDD voltage and should preferably be
connected to VDD when the USB is not used.
●VBAT = 1.55 V to 3.6 V
VBAT is the power supply for RTC, external clock 32 kHz oscillator and backup
registers (through power switch) when VDD is not present.
During power up and power down, the following power sequence is required:
●When VDD < 1 V, the other power supplies (VDDA , VDDUSB and V LCD ) must
remain below VDD + 0.3 V. During the power down VDD can temporarily become lower
than the other supplies only if the energy provided to the MCU remains below 1 mJ.
This allows the external decoupling capacitors to discharge with different time
constants.
●When VDD ≥ 1 V, all power supplies become independent.
An embedded linear voltage regulator is used to supply the internal digital power VCORE .
VCORE is the power supply for digital peripherals, SRAM1 and SRAM2. The Flash memory
is supplied by VCORE and VDD .