Silicon Laboratories BB50 User manual

UG550: BB50 Explorer Kit User's Guide
The BB50 Explorer Kit is an ultra-low cost, small form factor devel-
opment and evaluation platform for the EFM8BB50 Busy Bee 8-bit
microcontroller.
The BB50 Explorer Kit is focused on rapid prototyping and concept creation of multi-pur-
pose applications. It is designed around the EFM8BB50 MCU, which is an ideal device
family for developing energy-friendly embedded applications.
The kit features a USB interface, an on-board SEGGER J-Link debugger, one user-LED
and button, and support for hardware add-on boards via a mikroBUS™ socket and a
Qwiic® connector. The hardware add-on support allows developers to create and proto-
type applications using a virtually endless combination of off-the-shelf boards from mik-
roE, sparkfun, AdaFruit, and Seeed Studios.
TARGET DEVICE
• EFM8BB50 Busy Bee 8-bit microcontroller
(EFM8BB50F16I-A-QFN16)
• Pipelined 8-bit C8051 core with 50 MHz
maximum operating frequency
• 16 kB flash and 512 bytes RAM
KIT FEATURES
• User LED and push button
• 2.54 mm breakout pads
• mikroBUS™ socket
• Qwiic® connector
• SEGGER J-Link on-board debugger
• Virtual COM port
• USB-powered
SOFTWARE SUPPORT
• Simplicity Studio™
ORDERING INFORMATION
• BB50-EK2702A
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Table of Contents
1. Introduction ................................3
1.1 Kit Contents ...............................3
1.2 Getting Started ..............................3
1.3 Hardware Content .............................3
1.4 Kit Hardware Layout ............................4
2. Specifications ...............................5
2.1 Recommended Operating Conditions ......................5
2.2 Current Consumption ............................5
3. Hardware .................................6
3.1 Block Diagram ..............................6
3.2 Power Supply ..............................7
3.3 EFM8BB50 Reset .............................7
3.4 Push Button and LED............................7
3.5 On-board Debugger ............................8
3.6 Connectors ...............................8
3.6.1 Breakout Pads ............................9
3.6.2 MikroBUS Socket ...........................10
3.6.3 Qwiic Connector ............................11
3.6.4 Debug USB Micro-B Connector .......................11
4. Debugging ...............................12
4.1 On-board Debugger ............................12
4.2 Virtual COM Port .............................12
5. Schematics, Assembly Drawings, and BOM ...................13
6. Kit Revision History and Errata .......................14
6.1 Revision History .............................14
6.2 Errata .................................14
7. Board Revision History and Errata ......................15
7.1 Revision History .............................15
7.2 Errata .................................15
8. Document Revision History .........................16
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1. Introduction
The BB50 Explorer Kit has been designed to inspire customers to explore the Silicon Labs EFM8BB50 Busy Bee 8-bit microcontroller.
The kit includes a mikroBUS™ socket and Qwiic® connector, allowing users to add features to the kit with a large selection of off-the-
shelf boards.
Programming the BB50 Explorer Kit is easily done using a USB Micro-B cable and the on-board J-Link debugger. A USB virtual COM
port provides a serial connection to the target application. The BB50 Explorer Kit is supported in Simplicity Studio™ and a Board Sup-
port Package (BSP) is provided to give application developers a flying start.
Connecting external hardware to the BB50 Explorer Kit can be done using the breakout pads which present peripherals from the
EFM8BB50 Busy Bee such as I2C, SPI, UART, and GPIOs. The mikroBUS socket allows inserting mikroBUS add-on boards which in-
terface with the EFM8BB50 through SPI, UART, or I2C. The Qwiic connector can be used to connect hardware from the Qwiic Connect
System through I2C.
1.1 Kit Contents
The following items are included in the box:
• 1x BB50 Explorer Kit board (BRD2702A)
1.2 Getting Started
Detailed instructions for how to get started with your new BB50 Explorer Kit can be found on the Silicon Labs web pages:
silabs.com/dev-tools
1.3 Hardware Content
The following key hardware elements are included on the BB50 Explorer Kit:
• EFM8BB50 Busy Bee MCU with 50 MHz operating frequency, 16 kB flash, and 512 bytes RAM
• One LED and one push button
• On-board SEGGER J-Link debugger for easy programming and debugging, which includes a USB virtual COM port
• MikroBUS™ socket for connecting Click boards™ and other mikroBUS add-on boards
• Qwiic® connector for connecting Qwiic Connect System hardware
• Breakout pads for GPIO access and connection to external hardware
• Reset button
UG550: BB50 Explorer Kit User's Guide
Introduction
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1.4 Kit Hardware Layout
The layout of the BB50 Explorer Kit is shown below.
Top View
Push Button
35.6 mm
55.9 mm
Reset Button
Breakout Pads
USB Micro-B Connector
- Virtual COM port
- Debug access
- Packet trace
LED
Qwiic
Connector
EFM8BB50
On-board USB
J-Link Debugger
mikroBUS Socket
Figure 1.1. BB50 Explorer Kit Hardware Layout
UG550: BB50 Explorer Kit User's Guide
Introduction
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2. Specifications
2.1 Recommended Operating Conditions
Parameter Symbol Min Typ Max Unit
USB Supply Input Voltage VUSB — 5.0 — V
Supply Input Voltage (VMCU supplied externally) 1 , 2VVMCU 1.8 3.3 3.6 V
Operating Temperature TOP — 20 — ˚C
1 Not recommended for use with rechargeable Lithium batteries. Most Li-Ion and Li-Po cells exceed 3.6 V when fully charged.
2 When using the provided interfaces with add-on boards or other external hardware, tighter voltage limits might apply.
2.2 Current Consumption
The operating current of the board greatly depends on the application and the amount of external hardware connected. The table below
attempts to give some indication of typical current consumptions for the EFM8BB50 and the on-board debugger. Note that the numbers
are taken from the data sheets for the devices. For a full overview of the conditions that apply for a specific number from a data sheet,
the reader is encouraged to read the specific data sheet.
Table 2.1. Current Consumption
Parameter Symbol Condition Typ Unit
EFM8BB50 Current Con-
sumption1
IBB MCU current consumption in NORMAL mode (module
supply voltage = 3.3 V, f_SYSCLK = 49 MHz using
HFOSC, TAMB 25 ˚C)
2.79 mA
MCU current consumption in SNOOZE mode (module
supply voltage = 3.3 V, LFOSC running at 80 kHz, TAMB
25 ˚C)
9.3 µA
MCU current consumption in SHUTDOWN mode (module
supply voltage = 3.3 V, TAMB 25 ˚C)
0.24 µA
On-board Debugger Sleep
Current Consumption 2
IDBG On-board debugger current consumption when USB cable
is not inserted (EFM32GG12 EM4S mode current con-
sumption)
80 nA
1 From EFM8BB50 data sheet.
2 From EFM32GG12 data sheet.
UG550: BB50 Explorer Kit User's Guide
Specifications
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3. Hardware
The core of the BB50 Explorer Kit is the EFM8BB50 Busy Bee 8-bit microcontroller. Refer to section 1.4 Kit Hardware Layout for place-
ment and layout of the hardware components.
3.1 Block Diagram
An overview of the BB50 Explorer Kit is illustrated in the figure below.
Expandability
Debugging
J-Link
Debugger
USB Micro-B
Connector
Button and LED
EFM8BB50
Breakout Pads
Temperature
& Humidity
Sensor
Ambient
Light & UV
Sensor
Hall Effect
Sensor
User Button
& LED
Serial Flash
External connectivity
Qwiic
Connector
mikroBUS
Socket
Figure 3.1. Kit Block Diagram
UG550: BB50 Explorer Kit User's Guide
Hardware
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3.2 Power Supply
The kit is powered by the debug USB cable as illustrated in the figure below.
USB Micro-B LDO
5V0
IN OUT
Automatic
Isolation
3V3
VMCU
EFM8BB50
8-bit MCU
Peripherals
Peripherals
Peripherals
Peripherals
Figure 3.2. BB50 Explorer Kit Power Topology
The 5 volt power net on the USB bus is regulated down to 3.3 V using a low dropout regulator (LDO). An automatic isolation circuit
isolates the LDO when the USB cable is not plugged in.
Power can be injected externally on the VMCU net if the USB cable is removed and no other power sources are present on the kit.
Failure to follow this guideline can cause power conflicts and damage the LDO.
3.3 EFM8BB50 Reset
The EFM8BB50 can be reset by a few different sources:
• A user pressing the RESET button.
• The on-board debugger pulling the #RESET pin low.
3.4 Push Button and LED
The kit has one user push button, marked BTN0, that is connected to a GPIO on the EFM8BB50. The button is connected to pin P0.7
and it is debounced by an RC filter with a time constant of 1 ms. The logic state of the button is high while the button is not being
pressed, and low when the button is pressed.
The kit also features one yellow LED, marked LED0, that is controlled by a GPIO pin on the EFM8BB50. The LED is connected to pin
P1.2 in an active-high configuration.
EFM8BB50
BB50_LED0
BB50_BUTTON0
User
Button & LED
P0.7
P1.2
Figure 3.3. Button and LED
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Hardware
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3.5 On-board Debugger
The BB50 Explorer Kit contains a microcontroller separate from the EFM8BB50 Busy Bee that provides the user with an on-board J-
Link debugger through the USB Micro-B port. This microcontroller is referred to as the "on-board debugger", and is not programmable
by the user. When the USB cable is removed, the on-board debugger goes into a very low power shutoff mode (EM4S).
In addition to providing code download and debug features, the on-board debugger also presents a virtual COM port for general pur-
pose application serial data transfer.
The figure below shows the connections between the target EFM8BB50 device and the on-board debugger. The figure also shows the
presence of the Mini Simplicity Connector, and how this is connected to the same I/O pins.
Refer to chapter 4. Debugging for more details on debugging.
Mini Simplicity
Connector
RSTb/C2CK
P2.0/C2D
P0.4 (UARTx.TX)
P0.5 (UARTx.RX)
On-Board
J-Link
Debugger
VCOM_TX
VCOM_RX
DBG_C2CK
DBG_C2D
Host
PC USB
EFM8BB50
Figure 3.4. On-Board Debugger Connections
3.6 Connectors
The BB50 Explorer Kit features a USB Micro-B connector, breakout pads, a mikroBUS connector for connecting mikroBUS add-on
boards, and a Qwiic connector for connecting Qwiic Connect System hardware. The connectors are placed on the top side of the board,
and their placement and pinout are shown in the figure below. For additional information on the connectors, see the following sub chap-
ters.
1
2
3
4
5
6
7
8
9
6
Breakout Pads
mikroBUS
Sockets
USB Micro-B
Connector
J1
J2
P0.2
P0.1
GND
MikroBUS SPI COPI
VMCU
Qwiic
Connector
1
2
5
4
GND
5V
QWIIC I2C SDA
QWIIC I2C SCL
VCOM TX
VCOM RX
P0.0
P0.3
P2.0
P0.7
MikroBUS SPI CIPO
MikroBUS SPI SCK
MikroBUS SPI CS
RESET BUTTON
DBG C2D
DBG C2CK
3
P1.0
7
P1.1
8
P0.4
P0.6
P0.5 SPI0
SPI0
SPI0
SPI0
MikroBUS INT
MikroBUS UART RX
MikroBUS I2C SCL
MikroBUS I2C SDA
MikroBUS UART TX
SMB0
SMB0
UARTx
UARTx
LED0 P1.2
MikroBUS PWM TIMERx BUTTON0 MikroBUS ANALOG
ADC0
RSTb
Figure 3.5. BB50 Explorer Kit Connectors
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Hardware
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3.6.1 Breakout Pads
Seventeen breakout pads are provided and allow connection of external peripherals. The breakout pads are arranged in two rows and
contain a number of I/O pins that can be used with most of the EFM8BB50 Busy Bee's features. Additionally, the VMCU (main board
power rail), 3V3 (LDO regulator output), and 5V power rails are also exposed on the pads.
The pin-routing on the Busy Bee is flexible, so most peripherals can be routed to any pin on port 1 or 2. However, pins may be shared
between the breakout pads and other functions on the BB50 Explorer Kit. The figure in section 3.6 Connectors includes an overview of
the breakout pads and functionality that is shared with the kit.
Table 3.1. Breakout Pads Pinout
Pin Connection Shared Feature
Left-side Breakout Pins
1 GND Ground
2 5V Board USB voltage
3 P1.0 MikroBUS I2C_SDA, Qwiic I2C_SDA
4 P1.1 MikroBUS I2C_SCL, Qwiic I2C_SCL
5 P0.4 VCOM_TX, MicroBUS UART_TX
6 P0.5 VCOM_RX, MicroBUS UART_RX
7 P0.6 MikroBUS INT
8 P1.2 LED0, MikroBUS PWM
Right-side Breakout Pins
1 RSTb EFM8BB50 reset, active low
2 GND Ground
3 VMCU EFM8BB50 voltage domain
4 P0.2 MikroBUS SPI_COPI
5 P0.1 MikroBUS SPI_CIPO
6 P0.0 MikroBUS SPI_SCK
7 P0.3 MikroBUS SPI_CS
8 P2.0 DBG C2D
9 P0.7 BUTTON0, MikroBUS Analog
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Hardware
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3.6.2 MikroBUS Socket
The BB50 Explorer Kit features a mikroBUS™ socket compatible with mikroBUS add-on boards. MikroBUS add-on boards can expand
the functionality of the kit with peripherals such as sensors and LCDs. Add-on boards follow the mikroBUS socket pin mapping, and
communicate with the on-kit EFM8BB50 through UART, SPI, or I2C. Several GPIOs are exposed on the mikroBUS socket. MikroBUS
add-on boards can be powered by the 5V or VMCU power rails, which are available on the mikroBUS socket.
The pinout of the EFM8BB50 on the kit is made such that all required peripherals are available on the mikroBUS socket. The I2C sig-
nals are, however, shared with the Qwiic connector, and all mikroBUS signals are also routed to adjacent breakout pads.
When inserting a mikroBUS add-on board, refer to the orientation notch on the BB50 Explorer Kit, shown in the figure below, to ensure
correct orientation. Add-on boards have a similar notch that needs to be lined up with the one shown below.
mikroBUS
socket
Orientation notch
Figure 3.6. mikroBUS Add-on Board Orientation
The table below gives an overview of the mikroBUS socket pin connections to the EFM8BB50.
Table 3.2. mikroBUS Socket Pinout
mikro-
BUS Pin
Name
mikroBUS Pin
Function
Connection Shared Feature Suggested Peripheral Mapping
AN Analog P0.7 BREAKOUT_RIGHT9 ADC0.CH1
RST Reset P2.0 BREAKOUT_RIGHT8
CS SPI Chip Select P0.3 BREAKOUT_RIGHT7 SPI0.NSS
SCK SPI Clock P0.0 BREAKOUT_RIGHT6 SPI0.SCK
MISO SPI Main Input
Secondary Output
P0.1 BREAKOUT_RIGHT5 SPI0.CIPO
MOSI SPI Main Output
Secondary Input
P0.2 BREAKOUT_RIGHT4 SPI0.COPI
PWM PWM output P1.2 BREAKOUT_LEFT8 TIMERx.Tx
INT Hardware Interrupt P0.6 BREAKOUT_LEFT7
RX UART Receive P0.5 VCOM_RX, BREAKOUT_LEFT6 UARTx.RX
TX UART Transmit P0.4 VCOM_TX, BREAKOUT_LEFT5 UARTx.TX
SCL I2C Clock P1.1 QWIIC_I2C_SCL, BREAKOUT_LEFT4 SMB0.SCL
SDA I2C Data P1.0 QWIIC_I2C_SDA, BREAKOUT_LEFT3 SMB0.SDA
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