ARM Cordio BT4 Radio IP User manual

ARM-EPM-100746 4.0
Confidential
®
Cordio™ BT4 Radio IP
WH000
Customer Evaluation and
Demonstration Kit User’s Guide

© Copyright ARM Limited 2016. All rights reserved. WH000
ARM-EPM-100746 2.0 Confidential Page ii
Cordio™ BT4 Radio IP, Customer Evaluation and Demonstration Kit User’s Guide
© Copyright ARM Limited 2016. All rights reserved.
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Web address
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http://www.arm.com/products/system-ip/cordio-radio-cores/index.php

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Feedback
ARM limited welcomes feedback on both the product, and the documentation.
Feedback on this document
If you have any comments about this document, please send email to [e-mail] giving:
The document title
The document’s number
The page number(s) to which your comments refer
A concise explanation of your comments
General suggestion for additions and improvements are also welcome.
Support and Maintenance on the Cordio™ BT4 Radio IP
Please contact [e-mail] regarding any issues with the installation, content or use of this release
and a member of the ARM Product Support Group will log your query in the support database and respond as
soon as possible. Note that Support for this release of the product is only provided by ARM to a recipient who has
a current support and maintenance contract for the product.
Change history
Issue
Date
Release note part version
0.1
Feb 2015
Original Sunrise Micro Release
1.0
Jan 2016
ARM Release r2p3-00eac0
2.0
April 2016
Modified Sections 5.2 and 5.3 to add power profile picture, modified 3v
measurement test point instructions.
3.0
26 Jun 16
Released at r2p3-07rel0
4.0
29 Aug 16
Released at r3p0-00rel0

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1Contents
PRODUCT STATUS.............................................................................................................. II
WEB ADDRESS.................................................................................................................... II
FEEDBACK.......................................................................................................................... III
ARM LIMITED WELCOMES FEEDBACK ON BOTH THE PRODUCT, AND THE
DOCUMENTATION.............................................................................................................. III
FEEDBACK ON THIS DOCUMENT .................................................................................... III
GENERAL SUGGESTION FOR ADDITIONS AND IMPROVEMENTS ARE ALSO
WELCOME........................................................................................................................... III
SUPPORT AND MAINTENANCE ON THE CORDIO™ BT4 RADIO IP............................. III
CHANGE HISTORY............................................................................................................. III
1KIT CONTENTS ............................................................................................................ 1
1.1 Contents .............................................................................................................. 1
1.2 Default Jumper and Switch Positions.................................................................. 1
2DESCRIPTION .............................................................................................................. 3
2.1 Overview.............................................................................................................. 3
2.2 Features............................................................................................................... 4
3HARDWARE.................................................................................................................. 5
3.1 Block Diagram ..................................................................................................... 5
3.2 Power Selection and Switches ............................................................................ 6
3.2.1 5 Volt External Supply:.............................................................................. 6
3.2.2 Battery Supplies ........................................................................................ 7
3.2.3 1v / 3V Mode Switch.................................................................................. 7
3.2.4Power Domains......................................................................................... 8
3.3 Jumpers............................................................................................................... 9
3.3.1 Power Control FW Jumper........................................................................ 9
3.3.2 Current Measurement Jumpers:.............................................................. 10
3.3.3 LDO Jumpers: ......................................................................................... 10
3.3.4 UART/SWD Jumpers:.............................................................................. 11
3.3.5 Firmware / Demo Selection Jumpers:..................................................... 11
3.4 Headers ............................................................................................................. 12
3.4.1 J14 - Host UART: .................................................................................... 12
3.4.2 5 Volt Test Pins: ...................................................................................... 13
3.4.3 J26- I2C Pins:........................................................................................... 13
3.4.4 J22 –GPIOs (and LEDS):....................................................................... 13
3.4.5 J25 –AT Pins:......................................................................................... 13
3.4.6 J24- Host Serial Wire Debug:.................................................................. 13
3.4.7 J17 –SPI Bus.......................................................................................... 13
3.5 Buttons............................................................................................................... 14
3.5.1 BT4 Reset Buttons .................................................................................. 14
3.5.2 Wake-up/Discoverable Button................................................................. 15
3.5.3 Mbed Reset Button.................................................................................. 15
4FW MODES ................................................................................................................. 16
5CURRENT MEASUREMENT ...................................................................................... 17

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5.1 Considerations................................................................................................... 17
5.2 1 Volt Mode –Current Measurement ................................................................ 17
5.3 3 Volt Mode –Current Measurement ................................................................ 19
6TEST MODE................................................................................................................ 20
6.1 Radio Control and RF Evaluation...................................................................... 20
6.1.1 Use of Bluetooth Analyzer/Testers.......................................................... 20
6.1.2 Use of other RF Analyzers ...................................................................... 21
6.1.3 ARM Radio Control Tool ......................................................................... 22
6.1.4 Regulatory Testing .................................................................................. 23
7CMSIS DAP SUPPORT............................................................................................... 24
8DEMONSTRATION MODES AND INSTRUCTIONS:................................................. 25
8.1 Demo Preparation of Host Unit.......................................................................... 25
8.1.1 Phone/Tablet Requirements:................................................................... 25
8.1.2 Android App Installation: ......................................................................... 25
8.2 Demo and FW mode Jumper Selection:............................................................ 26
8.3 Running Demos................................................................................................. 27
8.3.1 Sensor Demo Screens: ........................................................................... 28
8.3.2 Beacon Demo Screens: .......................................................................... 28
8.4Changing Between Demo Modes:..................................................................... 29
9FW UPDATE PROCEDURE........................................................................................ 30
10 SCHEMATICS AND BOMS......................................................................................... 31

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1KIT CONTENTS
1.1 Contents
The CORDIO™ BT4 Evaluation and Development Kit contains the following items:
ARM Cordio BT4 Module (P/N: Cordio BT4 Module BD)
ARM Customer Evaluation Base Board (P/N: BT4-GEN2-EVAL)
USB power cable
USB to UART cable
Whip Antenna
Batteries: 3V Lithium Coin cell, 1.5V AAA Alkaline, and 1.2V Zinc/Air Button
USB FLASH Drive:
Customer Evaluation and Demonstration Board User’s Guides
Board Schematics
Radio Control Tool Utility and User’s Guide
Android Demo Application
Bluetooth Qualification Certificates
RF PHY Test Report
Product Marketing Literature
Cordio BT4 Technical Summary
1.2 Default Jumper and Switch Positions
The CORDIO Evaluation Board should ship with the jumpers and switches in the following positions. More
information about their configuration can be found in Sections 3.3 –3.5.

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Figure 1.2 –Default Jumper and Switch Positions

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2DESCRIPTION
2.1 Overview
The Cordio BT4 Module and Customer Evaluation Base Board is based upon the CORDIO™ BT4
Development SoC which is a low power, 40 pin 5 x5 mm QFN that contains the BT4 Radio IP plus an ARM
Cortex M0+™ host MCU.
Figure 2.1 –Cordio BT4 Module
The BT4 Development SoC in on 42 pin Module which contains the necessary discrete RF components
around the BT4 radio IP block within the SoC, the SoC’s External EEPROM and a Reset Button. The majority
of pins of the SoC are various voltage rails and I/O signals that are taken directly to the pins on the module.
This modular approach is taken to easily upgrade to future Cordio products.
The Customer Evaluation Base Board or “Eval Board” is a platform for the Module to plug into which enables
the evaluation of BT4 Radio Hard Macro’s RF performance and the low power consumption characteristics.
Supported by a Bluetooth Smart® protocol stack from ARM®, the evaluation platform supports the choice of
either a test FW mode or an operational / demo FW mode.
Schematics and Bill of Materials for both boards can be found in the Cordio BT4 Module and Eval board
Schematics document included on the USB thumb drive provided in the Evaluation kit.

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The platform can be powered from either an external 5v supply (Bench supply or USB cable) or from one of
three different types of batteries.
The board is mbed enabled allowing the user to utilize mbed tools and example source code as well as Keil
tools to develop custom FW for their ARM Cortex based SoC while it is still in development. It also supports
drag-n-drop FW programming of the Module.
Figure 2.1a –Gen 2, BT4 Eval Board, Top Side Figure 2.1b –Gen 2 BT4 Eval Board, Bottom Side
2.2 Features
Based upon ARM Cordio BT4 Development SoC
BT4 Radio IP Block with an ARM Cortex M0+Host MCU
Includes full Bluetooth Smart protocol stack
Selectable Power Sources:
5 Volt (USB or Bench supply), 3v CR2032 Lithium Coin Battery, 1.5v AAA Alkaline, 1.2v
Zinc/Air Hearing Aid Battery
Current measure test points on all power rails to radio IP block and Host MCU
Radio Control Tool: Tx and Rx evaluation via DTM HCI commands
SMA jack / Whip antenna
Board Usages:
RF Evaluation: (conductive or radiated)
Power consumption evaluation
Demo Modes: Temperature & Gyro sensors / UriBeacon mode
Development of Host MCU Firmware/Applications:
mbed enabled: On-line IDE with C/C++ compiler toolchain, SDK/open-source
libraries, developers collaborative forum, Keil tools. Supports drag and drop MCU
programing.

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3HARDWARE
Figure 3.1 - BT4 Customer Evaluation Board –Block Diagram
3.1 Block Diagram
The ARM Cordio BT4 Radio IP can be run in either a 1 volt or 3 volt mode/domain. The Cortex M0+Host
processor and its memories within the SoC are run at 1.2 volts. Level shifters are provided on all I/O buses to take
the SPI and I2C interfaces to 1.8 Volts and the UART and Serial Wire Debug lines to 3.3v. A separate mbed
controller from NXP runs at 3.3v and provides mbed development tools and drag-n-drop programming of the FW
for the BT4 Development SoC.
The entire block diagram is power-up when run in 5 volt line powered mode. Components within the red rectangle
are powered in any one of the three battery modes at 1.2 volts. The BT4 IP block is powered at either 1.0 or 3.3
volts depending on the S11 switch setting.

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3.2 Power Selection and Switches
The BT4 Customer Eval board can be powered by either an external 5v supply or from 1 of 3 on-board batteries.
Figure 3.2 - BT4 Customer Eval Board –Switch Descriptions
3.2.1 5 Volt External Supply:
An external 5 volt line supply can be provided either via the provided USB cable or via a 5v Bench supply attached
to TP1 and TP2 on the bottom left corner of the board. To select this power mode, slide the “Power Mode
Switch”, located along the center right edge of the board, to the “Line” position (towards the top of the board).
If “Line” mode is selected, the position of the 3 Battery selection slide switches on the lower right side of the board
do not matter. We recommend all 3 of these switches be slid to the right (towards the edge of the board) in the
“OFF” positions so that the batteries are not drained due to powering their respective on-board voltage regulators.

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3.2.2 Battery Supplies
The Eval board may be powered by one of three on-board batteries. First, the “Power Mode Switch” along the
center right edge of the board must be slid towards the bottom of the board in the “Battery” position (towards the 3
battery slide switches).
You may now select one of three batteries to power the board via the 3 Battery switches along the right lower side
of the board.
3.3V Lithium Coin cell
1.5 V AAA Alkaline cell
1.2V Zinc/Air Button battery
A given battery is selected by sliding a switch to the “ON” position (towards the center of the board).
PLEASE NOTE: Only one battery switch may be ON at any time. To prevent multiple power sources being
applied at the same time, if two or more of the 3 battery switches are “ON” at the same time, all 3 battery sources
will be disabled.
When the board is not in use, or is being transported, place all 3 battery switches in the “OFF” position (towards
the edge of the board) to conserve battery life. Simply placing the main Power Mode Switch in the “Line” position
does not disable the batteries from powering their respective regulators.
3.2.3 1v / 3V Mode Switch
The Cordio BT4 IP block can be powered via either a 1 volt or 3 volt rail. Switch S11, labeled as “BT4 Power” on
the top right corner of the board, selects what power mode the BT4 IP block will be run in.
The 1 volt mode can be selected regardless if the board is being powered by line power or any one of the 3
different battery supplies.
The 3 volt mode is only valid when powering the board via 5v line power or by the 3.3v Lithium battery. 3 volt
mode is not functional when powering the board via the 1.5v AAA or 1.2 Zinc/Air batteries.
PLEASE NOTE: DO NOT SWITCH POWER MODES WHEN POWER IS SUPPLIED TO THE BOARD AS THIS
MAY PERMENTANTLY DAMAGE THE SOC. Always power-down the board prior to moving this switch
position!

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3.2.4 Power Domains
Figure 3.2.3 - Block Diagram –Power Domains
All circuitry on the board is powered up when the board is run in “Line” mode on an external 5 volt supply as
shown by the grey shaded areas above. You MUST run in 5 volt mode to utilize the mbed controller or external
interfaces such as the Host UART during RF testing or FW programing.
The yellow shaded area indicates what blocks are active in either 3V Lithium battery or 1.5V AAA Alkaline battery
modes. These Battery modes support both the Sensor Demo and the Beacon demo. You cannot utilize test
modes (see Section 6) via the Host UART port while in Battery mode unless you are also hooked up to an
external 5v supply.
In 1.2v Zinc/Air battery mode, only the BT4 SoC is powered up as shown by the orange shaded area. This allows
the user to run the Beacon demo where no additional I/O is active. Unlike a production SOC, the BT4
Demonstration SoC relies on external SPI FLASH to store its firmware. This 1.8v FLASH is powered via the 1.5V
AAA battery during boot while the BT4 SoC is powered by the 1.2v Zinc/Air battery. Therefore, a 1.5V AAA battery
must be installed on the board (but 1.5 volt switch off) for Boot purposes when running in 1.2v mode. (Depending
on your board revision, the additional 1.8volt Gyro and Temperature sensors maybe active in 1.2v mode. These
sensors are also powered by the 1.5V AAA battery).
The table below shows the operational usage modes that are available in each of the 4 power source options.
Table 3.2.3 - Power Source vs. Operation Mode

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3.3 Jumpers
The following section provides a description of various jumpers and their function:
Figure 3.3 - BT4 Customer Eval Board –Jumper Descriptions
3.3.1 Power Control FW Jumper
J47 located along the lower left edge of the board determines how the on-board power regulators are controlled.
The on-board LDO regulators for both the 1.0 and 3.3 volt power rails can be either fixed to these levels –OR –
these regulators can supply a variable voltage level if under the control of the Radio Control Tool (RCT) as
described in Section 6.1.
The jumper on J47 should be placed in the upper “FIXED”position when the board is operating in Battery
power mode or when the board is in 5v Line Power mode but is NOT under RCT control. This will pre-set
the 1 volt and 3 volt rails to a fixed 1.0 and 3.3 volts respectively.
The lower position marked “RCT”should only be selected when a) The J19 FW jumpers are configured to
HCI or “Test”mode (Section 4), b) the board is being powered in 5 volt Line Power mode and c) when the
board is attached to a PC via both the USB to USB cable and the USB to UART cable and is under the
control of the Radio Control Tool or “RCT”.
The RCT has the ability to adjust both the 1 volt and 3 volt power rails to the BT4 Radio IP block within the SoC
for various power consumption tests. Setting of the voltage level on either power rail is done by the RCT user
interface.

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3.3.2 Current Measurement Jumpers:
The four “BT4 Current Measurement Jumpers”across the top of the board must ALWAYS be installed regardless
of what power source is chosen. These four jumpers are on power pins of the BT4 SoC and are made available to
measure the current draw on various parts of the BT4 Radio IP as well as the Host MCU. Below is the list of these
jumpers, the voltage rail name and a brief description. A more detailed explanation of current measurement is
provided in Section 5.
Table 3.3.1 - BT4 SoC Voltage Rails –Current Measurement Pins
3.3.3 LDO Jumpers:
When the board is powered by an external 5 volt power supply, 5 LDO’s generate the required on-board
voltage supplies. These 5 “LDO jumpers” (J12, 13, 29, 30, & 31) are all required to be installed if the board is
powered whether by an external 5V supply or through USB. (Population of these jumpers may be present in
Battery Power Mode but have no relevance). These jumpers are provided to measure current consumption or
provide a tap for an external power source for voltage margining. The relevant jumpers related to measuring
current consumption by the BT Radio IP Block is 1V_ADJ (J30) and 3V_ADJ (J31) as the other three LDO’s
power additional devices on the board. Below is a description of what each voltage rail powers on the board.
Table 3.3.2 - LDO Power Jumpers

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3.3.4 UART/SWD Jumpers:
The four UART/SWD Jumpers (J6-9) allow the BT4 SoC’s Host UART and Serial Wire Debug (SWD) interfaces to
be switched between the mbed controller and connector headers for external communications.
“UART/SWD jumpers” (J6-9) are located above the USB connector on the bottom left side of the board. Placing all
4 of the jumpers in their top position (marked “Header”) will connect the BT4 SoC Host UART to the J5 UART
header just to the right of USB connector. This is the default position that is used in most applications. This
position allows serial communications with Test equipment and PCs running ARM’s Radio Control Tool via J14.
Please note that the UART supports 3.3 volt signal level. A USB to UART cable is provided in the Kit that
supports 3.3 volt signal level. If you are connecting the Eval board to the RS-232 port of test equipment, you
will need to install a signal level shifting cable or adapter!
Placing these jumpers in the lower “mbed”position will connect the SWD and UART interfaces to the mbed
controller. This is used for drag-n-drop programing of the BT4 SoC’s FLASH. (See Section 9 on FW
programming). This also allows support of Keil tools via the USB connector. Please visit www.mbed.org to learn
more mbed tools and development community.
The Default positions for these jumpers are to have the UART jumpers (J8 & 9) to be in the top “Header”position
to allow UART communicates via the J14 UART header. Counter to this, the Serial Wire Debug (SWD) jumpers
(J6 & 7) should be in the lower “MBED”position to allow for FW updates and other functions as described in
Section 9).
3.3.5 Firmware / Demo Selection Jumpers:
The J19 Firmware/Demo Selection jumpers are located just under the lower right corner of the module. There are
two jumpers that determine the functionality of the board at boot time by loading the appropriate FW for either Test
Mode or Demo Mode. Please see Section 4 for additional information on these FW modes.

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3.4 Headers
The following headers are available on the BT4 Evaluation Board.
Figure 3.4 - Header Descriptions
3.4.1 J14 - Host UART:
Located on the bottom edge of the board, the Host UART port is provided to be able to communicate to the BT4
SoC and the BT4 Radio IP. The following board configuration is required:
The board must be powered via 5 volts (external supply or USB) to be able to use this port.
The UART Jumpers (J8 & J9) must be in the Header position (See Section 3.3.43.3.4).
The FW mode (J19) must be set to “HCI” FW mode (See Section 4).
The UART speed is 115200 baud, 8 bit, 1 stop, no flow control
Please note that the UART supports 3.3 volt signal level. A USB to UART cable is provided in the Kit that
supports 3.3 volt signal level. If you are connecting the Eval board to the RS-232 port of test equipment, you
will need to install a signal level shifting cable or adapter!

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3.4.2 5 Volt Test Pins:
Located on the lower left corner of the board are test points TP1 (Red, +5V) and TP2 (Black, GND). These are
voltage supply points to power the board from an external bench power supply.
The TP1 is tied to the same 5v input line as VBUS on the USB connector. The board is protected by a fuse for
both these 5 volt input signals.
3.4.3 J26- I2C Pins:
This connector is located along the center left edge of the board. This connector is provided to add additional off-
board I2C sensors for development and/or demonstration purposes. This 4 pin connector provides 1.8v output,
Gnd, SCL (Clock) and SDA (Data) signals. The I/O signals are level shifted from the 1.2 volt MCU interface to 1.8
volts.
3.4.4 J22 –GPIOs (and LEDS):
J22 is located just to the left of the Line/Battery power mode slide switch along the right edge of the board. The 4
pins on the top row of this header are 4 unused GPIO pins from the BT4 SoC (Level shifted to 3.3 volts). If the
user is utilizing the BT Eval Board as a firmware development platform, these lines can be programmed for
specific functions/indicators. A jumper can be placed across a pair of pins on J22 to connect the GPIO to a LED
for status indications.
Currently, GPIO 3 has functionality when the Eval board is in Demo mode (see Section 8.3), the other LEDs
currently have no function. Please check the LED numbers vs the GPIOs on the board schematics as the row of
LEDs underneath J22 do not line up directly with the corresponding GPIO jumper label above them on older
revisions of the board. This was corrected in revision C of the Evaluation board.
3.4.5 J25 –AT Pins:
J25 can be found on the top left hand corner of the board. This consists of 4 Analog Test Pins. These pins are
used for measurement in various trimming and calibration procedures. Further explanation on the use of these
pins is beyond the scope of this document.
3.4.6 J24- Host Serial Wire Debug:
This header can be found along the left edge of the board. These signals are level shifted to a 3.3 volt level and
are provided for debug purposes when developing custom FW on the Eval board platform. The SWD jumpers (J6
& J7) must be in the Header position to route the SWD signals to the J24 header (See Section 3.3.4).
3.4.7 J17 –SPI Bus
The J17 header can be found just under the BT4 module in the upper center of the board. It provides access to
the SPI bus of the BT4 Development SoC for use with external devices.

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3.5 Buttons
The figure below shows various push buttons on the Customer Evaluation Platform. This includes Reset of the
BT4 Development SoC, an interrupt button labeled as “WKUP” (Wake-up) and an mbed controller reset button.
The functions of these buttons are described below.
Figure 3.5 –Push Button Locations
3.5.1 BT4 Reset Buttons
The BT4 Reset buttons reset the entire BT4 Demonstration SoC which means it resets both the BT4 Radio IP
block and the host MCU. This Reset button is the Red momentary push button to the right of the module.
There is also a small black Reset button in the lower right corner on the module itself. It has the same function of
the Red button on the base platform board.
It is always a good idea to press either Reset button after power has been applied to the Evaluation Board.

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3.5.2 Wake-up/Discoverable Button
The momentary Blue button located near the lower left corner of the module is an interrupt button on one of the
BT4 Demonstration SoC’s GPIO lines. The button has 2 functions:
1) When the Customer Eval Board is in either of the Demo modes (Beacon or Sensor), the board will be in a
connectable mode for 30 seconds after power up. After that time, the board will shift into a low-power
operational mode. In Beacon mode, it will continue to beacon without being connectable via the provided
BT4 Browser application for configuration purposes. In Sensor mode, it will stop advertising altogether
and not be discoverable/connectable by the BT4 Browser application. Pressing the Blue button will return
the board to connectable mode again for 30 seconds. Once this time elapses, the board will re-enter its
low-power mode.
If jumpers on J22 are installed for the GPIO lines, the D4 LED with flash rapidly when the board is in a
connectable state. After 30 seconds have expired, the LED will flash slowly. The LED will also flash slowly
once it has made a wireless connection to a host device.
PLEASE NOTE: Depending on which FW version is installed on the module, pressing the Blue button
twice (about a second apart), may be required to place the unit into a connectable mode.
2) If the SoC has been placed in deep sleep mode, either by the Radio Control Tool or via HCI commands,
this Blue button will manually wake-up the SoC from its deep sleep state. This functionality is only
available in Test/HCI pass-through mode.
3.5.3 Mbed Reset Button
The mbed controller reset button is a Black momentary push button located in the lower left portion of the board.
This is provided only for FW updates for the mbed controller and has nothing to do with the operation of the BT4
Demonstration SoC. Under normal operation, this button will not be used. If pressed, it may momentarily interrupt
communication between the Customer Eval Board and the Radio Control Tool.