The BM71-XPro board is a hardware platform designed to evaluate and test the capabilities of the BM71 Bluetooth
RF module. The BM71-XPro board provides multiple options for rapid prototyping and developing applications. The
board is supported by Atmel Studio, an integrated development platform, which provides predefined applications and
examples.
®
Features
• USB-UART Bridge (MCP2200) for Host PC Operation
• On Board 3.3V LDO for Power Regulation
• On Board SPI Flash for Storing Firmware Images (DFU OTA)
• Test Point for GPIO Pin (P1_3)
• Reset Push Button
• DIP Switch to Control:
– BM71 operation mode
– LED
– GPIO pin
• Passive RC Filters for PWM and ADC Inputs
• Atmel Studio (ASF3), to Provide Predefined Application Examples
The Microchip Website.................................................................................................................................35
The following figure shows the layout of the BM71-XPro board and illustrates the components available in the board:
Figure 1-1. BM71-XPro Board
BM71-XPro
Kit Contents
1.1 Reference Documentation
Microchip offers several smartphone applications, available for free in both the App Store (iPhone®) and Google
Play™ store (Android™), to evaluate the BM71 module. For details on the currently available apps, please refer to the
BM71 XPro webpage.
For further information, refer to the following:
• BM70/71 Bluetooth® Low Energy (BLE) Module Data Sheet (DS60001372)
• BM70/71 Bluetooth® Low Energy Module User’s Guide (DS50002542).
A description of some of the key features in the BM71-XPro board is provided below. Refer to Figure 1-1 for details of
the kit contents.
2.1 Power Supply
Power the BM71-XPro kit using any of the power sources listed below:
• Micro USB port (J1)
• XPro Connector
Use the J2 header for selecting between these power supply options using a jumper. The green LED (LD1) indicates
that the board is powered by a micro-USB. The micro-USB has ESD and overcurrent protection, and the input to the
module is controlled via an LDO (U1). The BM71-XPro board can be operated in a standalone mode when powered
via the micro-USB.
2.2 USB-UART Bridge
The MCP2200 in the BM71-XPro board provides the option to evaluate the BM71 module in Standalone mode. By
default (out of the box), the BM71 module is set to operate in Auto mode. So, the module, once powered via the
micro-USB, will be able to connect to a peer Bluetooth Low Energy device and open a data pipe for data transfer.
Refer to 3.1 Connecting the BM71 XPRO to MBD App in Auto Mode for details. Apart from powering the board, the
micro-USB port can also be used to evaluate and test the module via a host PC. Microchip provides emulation tools,
such as a UI tool, auto pattern tool, and manual tool (refer to BM71 webpage for details) to evaluate the BM71 via a
host PC. The BM71 module can be set to operate in Manual mode for complete control or in Auto mode for a simple
data pipe application.
BM71-XPro
Hardware Features
2.3 XPRO Connector
The BM71-XPro board has an Xplained Pro (XPRO) header to offer connectivity and control from a host MCU. The
header is based on a standard extension header and its pin details are specified in the following table. The headers
have a pitch of 2.54 mm. For details on the operating the BM71-XPro via a host MCU Xplained Pro board, refer to
3.3 Connecting the BM71-XPro to MBD App in Manual Mode (Host PC).
Table 2-1. Extension Header (J1) Pin Description
Pin#Pin nameDescription
1IDID Chip communication
2GNDGround
3ADC1Connected to pin P2_0 to set system configuration
The DIP switch has three switches which provide the functions described in the following table.
Table 2-2. DIP Switch Functions
Switch#Function
1Manually set the BM71 system configuration. Connected to pin P2_0.
• ON: Memory Programming mode
• OFF: Application mode
2Turn the Blue LED (LD4) ON/OFF
3Control the GPIO pin P1_3
2.5 Reset Switch
The Reset push button is connected to the BM71 module reset line. When the Reset button is pressed, it drives the
reset line to ground. The BM71-XPro board has an on-board voltage detected reset IC (MCP112) connected to the
Reset pin of the BM71.
2.6 Current Measurement Header
A J3 header can be used for current measurement.. All power to the BM71-XPro is routed through these header pins.
To measure the power consumption of the module, remove the jumper and replace it with an ammeter. To make sure
only the power consumption of the BM71 module is measured, turn off the blue LED using switch #2 of the DIP
switch.
2.7 On-board SPI Flash
An SST25VF080B SPI Flash memory is included in the BM71-XPro board for nonvolatile firmware storage. This can
be used to update the device firmware for the BM71 or the host MCU.
Note: BM71 Xplained Pro board is intended for use for development, demonstration or evaluation purposes only. It
is not a finished appliance, nor is it intended for incorporation into or reference design for finished appliances that are
made commercially available.
Every effort has been made to minimize electromagnetic emissions from the product. However, under certain
conditions, the system (this product connected to a host application circuit via Xplained Pro extension header for
communicating with External SPI Flash) may emit individual electromagnetic component frequencies which exceed
the maximum values allowed by the standards. The frequency and magnitude of the emissions will be determined by
several factors, including layout and routing of the application with which the product is used. The recommendation is
to add external series resistors on the Xplained Pro Extension Header SPI signals to the External SPI Flash if the
product causes emissions above the permissible limits of the standard. For reference for the BM71 module
placement and layout guidelines please refer the BM71 Module datasheet.
The BM70/71 module supports following modes, which affect the overall Bluetooth Low Energy and hardware
behavior:
• Auto operation configuration or Auto mode: By default, the BM70/71 module is set to operate in the Auto
mode. The Auto mode restricts the available Bluetooth Low Energy operations by only allowing the Bluetooth
Low Energy peripheral to act as a raw data pipe. This is compatible with hosts who only require the BM70/71
module to act as a virtual UART cable between the host and the remote peer device.
• Manual operation configuration or Manual mode: Manual operation provides the host MCU a lot more control
and functional options over the BM71 Bluetooth Low Energy protocol and operation in comparison to the Auto
Operation mode. This configuration is used by a host MCU to leverage the flexibility and feature set offered by
both the Bluetooth Low Energy protocol and the BM71 module (for example: private services and
characteristics).
Note: For more details, refer to the Section 1.1 Operation Overview in the BM70/71 Bluetooth Low Energy Module
User’s Guide (DS50002542).
The simplest method to start evaluating the BM71 is to connect it to a host PC that supports USB CDC virtual COM
(serial) ports and operates in Auto mode. In this mode, the user can directly connect to the BM71 from a peer device
(phone app) and open a raw data pipe. Refer to 3.1 Connecting the BM71 XPRO to MBD App in Auto Mode for
connection procedure. See 3.2 Configuring the BM71 Module to Operate in Manual Mode (Host PC) and 3.3
Connecting the BM71-XPro to MBD App in Manual Mode (Host PC) for an example of Manual mode of operation.
BM71-XPro
Module Configuration
3.1 Connecting the BM71 XPRO to MBD App in Auto Mode
Hardware/Software required:
• BM71-XPro board; Mini-USB cable.
• A PC host supporting USB CDC virtual serial port. BM71-XPro board uses MCP2200 USB to UART bridge. The
drivers can be downloaded from http://www.microchip.com/MCP2200.
• Terminal Emulator application. TeraTerm or CoolTerm is recommended.
• Microchip MBD app for iOS or Android. Available in:
– App Store (iOS) for iPhones.
– Google Play Store for Android phones.
By default, the BM71 module is set to operate in Auto mode. For details on the Auto mode of operation on the BM71
module, refer to section 1.1.2.1 in the BM70/71 User’s Guide (DS50002542).
The procedure to connect the BM71-XPro board to a peer device (phone/table) via host PC is given below:
1.Ensure that the BM71-XPro board is configured as follows:
1.1.Jumper on the J2 header is closed to select USB power option.
1.2.The current measurement jumper on J3 is present.
1.3.Switch 1 (system configuration) on the DIP switch is set to OFF.
1.4.Switch 2 (blue LED) on the DIP switch is set to ON.
2.Connect the BM71-XPro board to a host PC using the mini-USB cable. Ensure that green LED (LD1) is solid
ON indicating USB power.
3.Connect BM71-XPro to a PC host using micro-USB cable.
3.1.Verify the virtual COM port is enumerated on a host PC. If the COM port does not enumerate, the
MCP2200 drivers may be missing from the host PC. If needed, the drivers can be downloaded from
the www.microchip.com/MCP2200 webpage.
3.2.Press the Reset button (SW1) and verify that the blue LED (LD4) is flashing intermittently.
4.Start the Terminal Emulator software. In this example, TeraTerm is used. Configure the serial port settings of
the enumerated COM port as shown in the following figure.
11. In the serial emulator application (TeraTerm), enter any text and this should show up in the transparent UART
page in the app.
3.2 Configuring the BM71 Module to Operate in Manual Mode (Host PC)
Hardware/Software required:
• BM71-XPro board; Mini-USB cable.
• A PC host supporting USB CDC virtual serial port. BM71-XPro board uses MCP2200 USB to UART bridge. The
drivers can be downloaded from http://www.microchip.com/MCP2200.
• BM71 emulator tools: UI Tool. These tools can be download from the BM71 webpage.
The procedure to change the BM71 to Manual mode via host PC is given below:
1.Ensure that the BM71-XPro board is configured as follows:
1.1.Middle jumper on J2 is closed to select USB power option.
1.2.The current measurement jumper on J3 is present.
1.3.Switch 2 (blue LED) on the DIP switch is set to ON.
2.Connect the BM71-XPro board to the host PC using the mini-USB cable. Ensure that the green LED (LD1) is
solid ON indicating USB power.
3.Connect BM71-XPro board to the host PC using micro-USB cable. Verify the virtual COM port is enumerated
on the host PC. If the COM port does not enumerate, the MCP2200 drivers may be missing from the host PC.
If needed, the drivers can be downloaded from the http://www.microchip.com/MCP2200 web page.
4.Set switch 1 (system configuration) on the DIP switch to ON. Press the Reset button (SW1). The blue LED
(LD4) should turn to a solid ON.
5.Open the UI tool (see the following figure) and Click on ‘Load’.