Ublox EVK-ANNA-B112 User manual

EVK-ANNA-B112
Evaluation Kit for ANNA-B112 Bluetooth 5 low energy
modules
User Guide

Abstract
This document describes how to set up the EVK-ANNA-B112 evaluation kit to evaluate ANNA-B112
series standalone Bluetooth®
5 low energy modules. It also describes the different options for
debugging and the development capabilities included in the evaluation board.
www.u-blox.com
UBX-18018539 - R01

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Document Information
Title EVK-ANNA-B112
Subtitle Evaluation Kit for ANNA-B112 Bluetooth 5 low energy modules
Document type User Guide
Document number UBX-18018539
Revision and date R01 5-Jun-2018
Disclosure Restriction
This document applies to the following products:
Product name Type number Firmware version PCN reference
EVK-ANNA-B112U EVK-ANNA-B112U-00 -
EVK-ANNA-B112C EVK-ANNA-B112C-00 -
u-blox or third parties may hold intellectual property rights in the products, names, logos and designs included in this
document. Copying, reproduction, modification or disclosure to third parties of this document or any part thereof is only
permitted with the
express written permission of u-blox.
The information contained herein is provided “as is” and u
-blox assumes no liability for its use. No warranty, either express or
implied, is given, including but not limited
to, with respect to the accuracy, correctness, reliability and fitness for a particular
purpose of the information. This document may be revised by u
-blox at any time without notice. For the most recent
documents, visit www.u
-blox.com.
Copyright © u
-blox AG.

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Contents
Document Information................................................................................................................................2
Contents ..........................................................................................................................................................3
1Product description ..............................................................................................................................4
1.1 Overview........................................................................................................................................................ 4
1.2 Kit includes ................................................................................................................................................... 5
1.3 Key features .................................................................................................................................................5
1.4 EVK-ANNA-B112 block diagram ............................................................................................................... 6
1.5 Connectors ................................................................................................................................................... 7
1.6 Powering options......................................................................................................................................... 7
1.6.1 Selecting the power configuration jumpers.................................................................................. 8
1.6.2 Default power, 3.3 V ........................................................................................................................... 9
1.6.3 Battery powered, 3 V........................................................................................................................ 10
1.6.4 Battery powered with protection diode, 2.7 V............................................................................. 10
1.6.5 External supply................................................................................................................................... 11
1.6.6 Raspberry Pi HAT............................................................................................................................... 11
1.7 Arduino interface .......................................................................................................................................12
1.7.1 Arduino shield compatibility........................................................................................................... 13
1.8 Raspberry Pi compatible interface ........................................................................................................ 14
1.8.1 Powering considerations................................................................................................................. 16
1.8.2 UART ................................................................................................................................................... 16
1.8.3 EEPROM support .............................................................................................................................. 16
1.9 Buttons and LEDs ......................................................................................................................................17
1.10 Disconnecting ANNA signals from board peripherals........................................................................17
1.11 Software debug options .......................................................................................................................... 19
2Setting up the evaluation board.................................................................................................... 20
2.1 Evaluation board setup ............................................................................................................................20
2.2 Starting up .................................................................................................................................................20
2.2.1 EVK-ANNA-B112 ................................................................................................................................20
2.2.2 EVK-ANNA-B112 SDK .......................................................................................................................20
2.3 Getting the latest software ....................................................................................................................20
Appendix ........................................................................................................................................................ 21
APlacement and Schematics.............................................................................................................. 21
BGlossary ..................................................................................................................................................27
Related documents ................................................................................................................................... 28
Revision history.......................................................................................................................................... 28
Contact...........................................................................................................................................................29

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1Product description
1.1 Overview
The u-blox EVK-ANNA-B112 evaluation kit is a versatile development platform that allows quick
prototyping of a variety of extremely low-power Internet of Things (IoT) applications, using Bluetooth
5, Bluetooth mesh and NFC.
The u-blox EVK-ANNA-B112 boards are available in the following two variants depending on the
required antenna:
•EVK-ANNA-B112U, with an ANNA-B112U module including u-blox connectivity software, and an
antenna connector for connecting to external antennas
•EVK-ANNA-B112C, with an ANNA-B112C module including u-blox connectivity software and an
internal antenna (a unique 2.4 GHz antenna in the SIP).
The evaluation board provides access to all 25 IO pins and interfaces available on the
ANNA-B112 modules through a variety of connectors and interfaces, including Arduino™ Uno R3 and
Raspberry Pi header connectors.
The stand-alone ANNA-B112 is based on the Nordic Semiconductor nRF52832 chip. The nRF52832
uses an Arm®Cortex®-M4F microcontroller with 512 kB internal flash and 64 kB RAM, running at a
system clock of 64 MHz. The evaulation board provides simple USB drag-n-drop programming and a
SEGGER J-Link debug interface that can be used with the open CPU variants of the EVK. Nordic
provides a free Software Development Kit (SDK) with a broad selection of drivers, libraries, and
example applications that can be used for rapid prototyping.
Figure 1: EVK-ANNA-B112 evaluation boards

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Figure 2: Left: EVB ANNA-B112U including U.FL connector; Right: EVB ANNA-B112C including an internal antenna.
Figure 3: Left: EVB ANNA-B112U including NFC antenna; Right: EVB ANNA-B112U including NFC antenna, turned 180
degrees. Both options are valid.
1.2 Kit includes
The EVK-ANNA-B112 evaluation kit includes the following:
•EVK-ANNA-B112 evaluation board
•2.4 GHz external antenna with U.FL connector (only in EVK-ANNA-B112U)
•NFC antenna
•USB cable
•Quick Start card
1.3 Key features
•u-blox ANNA-B112 Bluetooth low energy module based on the Nordic nRF52832 chipset:
oBluetooth 5 support
oBluetooth mesh
oNFC tag functionality
oIntegrated Arm® Cortex®-M4F microcontroller with 512 kB flash, 64 kB RAM, and 64
MHz system clock
oWide 1.7-3.6 V supply range
•The ANNA-B112 module supports different interfaces that can be configured to any of the 25
available IO pin(s):
o8 analog capable inputs

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o12 PWM capable outputs
o3x SPI
o1x UART with HW flow control
o2x I2C
o1x I2S
•Full UART to USB converter with a Virtual COM port that allows control of the extended UART
features of the u-blox connectivity software
•On-board J-Link debugger/programmer:
oMass Storage Device interface to PC, for drag-n-drop programming
oDebug port
oAn additional Virtual COM port that, for example, may be connected to add-on boards
or to a debug UART on the ANNA-B112
•RGB LED and push buttons
•Arduino UNO R3 and Raspberry Pi compatible pin header interfaces
•Jumper headers and level shifters allow for flexible powering options of the ANNA-B112 module,
even with full board support. They isolate the module entirely and control each power net
separately in order to precisely measure low power applications or disconnect only unused parts
of the board to save battery life.
•Multiple board power supply options:
o5-12 V power plug
o5 V USB supply
o5-12 V Arduino VIN input
•Battery holder supporting CR2032 coin cell batteries
1.4 EVK-ANNA-B112 block diagram
The block diagram of EVK-ANNA-B112 is shown in Figure 4.
Figure 4: EVK-ANNA-B112 block diagram
The block diagram shows the major interfaces and internal connections of the EVK-ANNA-B112. The
following sections describe in detail how the different interfaces are connected and used, and how
the evaluation board may be configured to suit the needs of the user.

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1.5 Connectors
Figure 5 shows the available connectors on the EVK-ANNA-B112 and their layout. Table 1 describes
the connectors and their uses in detail.
Figure 5: Available connectors and their pinout
Connector
annotation
Function Description
J5 Power supply 2.1 mm power jack, the center pin is the positive terminal. 5 – 12 V input.
J17 Power supply Pin header that can be used to connect external power supplies. 5 – 12 V input.
BT1 Battery holder CR2032 coin cell battery holder. CR2032 usually has a 3 V potential when fully
charged.
J11 NFC antenna
connector
Pin header that connects to the u-blox NFC antenna included in the kit.
J10 2.4 GHz RF antenna
connector
U.FL coaxial connector that can be used to connect antennas or RF equipment. This
connector is included only in the EVK-ANNA-B112U.
J12 Cortex Debug
connector
10-pin, 50 mil pitch connector that can be used to connect external debuggers to
the ANNA-B112 module. The ANNA-B112 modules support Serial Wire debug (SWD)
and Serial Wire Viewer, but not JTAG debug.
J21 Cortex Debug+ETM
connector
20-pin, 50 mil pitch connector. This extended connector has the same features as
J12, but also allows for instruction trace operations via the Embedded Trace
Macrocell (ETM) of the Cortex®-M4F microcontroller inside the ANNA-B112 module.
This requires a special external debugger. Note that the 50 mil pitch pin header is
not soldered onto the evaluation board by default.
J8 Power supply, COM
port and debug USB
The main USB connector that is used to program, debug, and communicate with the
ANNA-B112 module. It can also be used to power the entire board.
Table 1: EVK-ANNA-B112 connector description
1.6 Powering options
Power can be supplied to the board in one of the following ways:
•Via the USB connector, J8
•Using the power jack, J5
•Using the Arduino interface VIN pin
•Using the pin header J17

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•Plugging in a battery to the battery holder BT1
These power supply sources are distributed to the rest of the board as shown in Figure 6.
Figure 6: Block diagram of the power net distribution
1.6.1 Selecting the power configuration jumpers
The EVK-ANNA-B112 offers flexible powering options for the ANNA-B112 module and the board itself.
To configure this, jumpers are added to or removed from pin headers, shorting two of the pins
together and connecting or disconnecting different power nets on the evaluation board. Figure 7
shows the location of the power configuration jumper headers. The 3V3 net is supplied by the board
and will always be powered as long as any of the power sources shown in Figure 6 are connected. The
3V3 net will not provide power unless a jumper is added to jumper header J7.
Figure 7: Jumper headers J7 and J22 are used to select power configurations

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Connector
annotation
Pin
number
Schematic
net name
Description
J7 1 3V3 Regulated 3.3 V net. This net is supplied by the board and will always be powered
as long as a power source is connected.
2 3V3_PI Connects to the Raspberry Pi header’s (J14) 3V3 pins. If a Raspberry Pi is
connected, this net must be floating to prevent back currents. If a HAT is
connected, this net can be shorted to the EVK 3.3 V supply to power the HAT.
3 VBAT_DIODE To protect the battery from current back surges, connect the battery to the
ANNA-B112 module via a protection diode using this pin.
4 VDD_ANNA Connects to J22 pin 3, from where it can be connected to the module supply pin or
somewhere else.
5 VBAT Battery + terminal
6 VDD_ANNA Connects to J22 pin 3, from where it can be connected to the module supply pin or
somewhere else.
7 3V3 Regulated 3.3 V net. This net is supplied by the board and will always be powered
as long as a power source is connected.
8 VDD_ANNA Connects to J22 pin 3, from where it can be connected to the module supply pin or
somewhere else.
9 3V3 Regulated 3.3 V net. This net is supplied by the board and will always be powered
as long as a power source is connected.
10 VDD_MCU Supply net for the board functions not directly connected to the ANNA-B112
module; Interface MCU, USB hub, UART to USB converter etc.
11 GND Ground net.
12 GND Ground net.
J22 1 VCC ANNA-B112 module voltage supply that connects to the module VCC pin. Shorted
to the VCC_IO net via 0 Ωresistor R4 by default.
2 VCC_IO VCC_IO pin not connected.
3 VDD_ANNA Connects to J7 pins 4, 6 and 8. Short J22 pins 1 and 3 allow the EVK to power the
ANNA-B112 module.
4 VDD_IO Supply net for LEDs and peripherals connected directly to the ANNA-B112 module.
Short J22 pins 2 and 4.
5 GND Ground net.
6 GND Ground net.
Table 2: Pinout of jumper headers J7 and J22 used to configure the board power nets
The following sections describe different jumper configurations and power scenarios that is available
on the board, including the default configuration.
⚠Check the jumper positions carefully; if a jumper is connected in a wrong way, it can permanently
damage the components that are on the board or connected to it.
1.6.2 Default power, 3.3 V
This is the default power configuration for the evaluation board, and the jumpers are installed out of
the box with this power configuration. All board peripherals are powered up, the ANNA module is
directly supplied by the board and everything is running at 3.3 V.
Figure 8: Jumper positions for default power configuration

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Connector
annotation
Add jumper
to pins
Description
J7 7, 8 Selects the board regulated 3.3 V net as source for the VDD_ANNA net.
9, 10 Powers up the Interface MCU, USB hub, and UART to USB converter with 3.3 V.
J22 1, 3 Powers up the ANNA module. The ANNA VCC and VCC_IO pins are connected to the selected
source for the VDD_ANNA net.
2, 4 Powers up the peripherals directly connected to ANNA such as LEDs and external memory
with the ANNA supply voltage.
Table 3: Jumper positions for default power configuration
1.6.3 Battery powered, 3 V
When using a battery, Figure 9 shows the default configuration. The battery voltage is connected to
VDD_ANNA, which in turn, is connected to the ANNA-B112 VCC supply. If needed, a jumper can be
added to J22 pins 2 and 4 to supply LEDs and other peripherals with power, as long as this does not
exceed the maximum current rating of the battery. If the ANNA module has to be configured, the
VDD_MCU net can be connected to enable PC communications by adding a jumper to J7 pins 9 and
10.
Figure 9: Jumper positions for battery powered operation, two jumpers are optional
Connector
annotation
Add jumper
to pins
Description
J7 5, 6 Selects the battery connected to the battery holder as source for the VDD_ANNA net.
9, 10 (Optional) Powers up the Interface MCU, USB hub, and UART to USB converter with 3.3 V.
J22 1, 3 Powers up the ANNA module. The ANNA VCC and VCC_IO pins are connected to the selected
source for the VDD_ANNA net.
2, 4 (Optional) Powers up the peripherals directly connected to ANNA such as LEDs and external
memory with the ANNA supply voltage.
Table 4: Jumper positions for battery powered operation, two jumpers are optional
1.6.4 Battery powered with protection diode, 2.7 V
This use case is meant to protect the battery from current back surges. When using the NFC
interface, there is a risk that the applied electromagnetic field can cause back surges that will
typically damage a non-chargeable battery. To prevent this damage, a schottky diode can be added
in series to the battery, which will block any back current surges. A jumper should then be added to
J7 pins - 3 and 4 instead of 5 and 6.
The diode will lower the voltage level of the battery by about 0.3 V.
Figure 10: Jumper positions for battery powered operation with a protection diode, two jumpers are optional

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Connector
annotation
Add jumper
to pins
Description
J7 3, 4 Selects the diode protected battery as a source for the VDD_ANNA net.
9, 10 (Optional) Powers up the Interface MCU, USB hub, and UART to USB converter with 3.3 V.
J22 1, 3 Powers up the ANNA module. The ANNA VCC and VCC_IO pins are connected to the selected
source for the VDD_ANNA net.
2, 4 (Optional) Powers up the peripherals directly connected to ANNA such as LEDs and external
memory with the ANNA supply voltage.
Table 5: Jumper positions for battery powered operation with a protection diode, two jumpers are optional
1.6.5 External supply
When measuring current consumption or performing other ANNA-B112 module characterization
measurements, it can be useful to power the module with an external source such as a DC power
analyzer. In such a case, all jumpers can be removed and the required supply nets can be fed
externally by connecting to the pin headers. For example, the ANNA-B112 module can be powered by
connecting an external supply directly to the J22 pin 1 and GND.
☞Take care that unpowered parts of the board are properly isolated. If a voltage is applied to the
signal of an unpowered device, current might leak through various protection circuits of the
device. This might give false readings when measuring current consumption etc.
Figure 11 below shows a few optional jumper connections that can be helpful when supplying the
module with an external supply.
Figure 11: Optional jumper positons while using an external power supply
Connector
annotation
Add jumper
to pins
Description
J7 7, 8 (Optional) Selects the board regulated 3.3 V net as a source for the VDD_ANNA net.
9, 10 (Optional) Powers up the interface MCU, USB hub, and UART to USB converter with 3.3 V.
J22 3, 4 (Optional) Powers up the peripherals directly connected to ANNA such as LEDs
and external memory with the selected source for the VDD_ANNA net.
Table 6: Optional jumper positons while using an external supply
1.6.6 Raspberry Pi HAT
When connecting a HAT to the Raspberry Pi interface, the following jumper configuration can be
used. Depending on how the ANNA module should communicate with a test PC over USB or with the
HAT, the VDD_MCU net can be left unpowered.
The 3V3_PI supply net must only be powered when connecting to a Raspberry Pi expansion board
(HAT). If connecting to a Raspberry Pi board, the jumper must be disconnected.
Figure 12: Jumper configuration when connected to a Raspberry Pi HAT

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Connector
annotation
Add jumper
to pins
Description
J7 1,2 Connects the 3V3_PI net to the regulated 3.3 V supply.
7, 8 Selects the board regulated 3.3 V net as a source for the VDD_ANNA net.
9, 10 (Optional) Powers up the Interface MCU, USB hub, and UART to USB converter with 3.3 V.
J22 1, 3 Powers up the ANNA module. The ANNA VCC and VCC_IO pins are connected to the selected
source for the VDD_ANNA net.
2, 4 (Optional) Powers up the peripherals directly connected to ANNA such as LEDs and external
memory with the ANNA supply voltage.
Table 7: Jumper configuration when connected to a Raspberry Pi HAT
1.7 Arduino interface
The EVK-ANNA-B112 includes a set of pin headers and mounting holes that are compatible with
certain Arduino or Arduino inspired shields. Figure 13 shows the layout of the Arduino interface and
Table 8 explains the pinout in more detail. Section 1.7.1 describes what specifications must be met
for a shield to be compatible for use with the EVK-ANNA-B112.
☞The silk screen text on EVB marked UBXH60-0000474 J3 pin 6 shall be IO_31.
Figure 13: Pin headers that are compatible with some Arduino shields
Conn. Pin
No.
Arduino
pin
Description Schematic
net name
nRF52
pin
u-blox connectivity and alternate
functions with notes
J1 1 N/C Not Connected - - Not connected
2 IOREF I/O reference voltage level.
Selectable by user to 1.7 – 3.6 V
VDD_IO - See section 1.6
3 RESET Reset signal input. Active low logic RESET_N P0.21
4 3.3V 3.3 V DC regulated supply output 3V3 -
5 5V 5 V regulated supply output 5V - Cannot be used as supply input, use
VIN instead. Only supplied by USB
VBUS.
6 GND Ground GND GND
7 GND Ground GND GND
8 VIN External DC supply input, 5 – 12 VDC VIN -

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J2 1 A0 Analog input IO_24 P0.04 Analog function capable IO
2 A1 Analog input IO_23 P0.05 Analog function capable IO
3 A2 Analog input IO_28 P0.28 Analog function capable IO
4 A3 Analog input IO_27 P0.29 Analog function capable IO
5 A4 Analog input UART_DSR/
IO_26
P0.30 Analog function capable IO,
UART_DSR signal on ANNA-B1
6 A5 Analog input
UART_DTR/
IO_25
P0.31 Analog function capable IO,
UART_DTR signal on ANNA-B1
J3 1 D0/RX Digital I/O, UART RX UART_RXD P0.02 UART_RXD signal on ANNA-B1
2 D1/TX Digital I/O, UART TX UART_TXD P0.03 UART_TXD signal on ANNA-B1
3 D2 Digital I/O UART_CTS P0.19 UART_CTS signal on ANNA-B1
4 D3 Digital I/O UART_RTS P0.11 UART_RTS signal on ANNA-B1
5 D4 Digital I/O IO_29 P0.27 RED
6 D5 Digital I/O IO_31 P0.26 BLUE
7 D6 Digital I/O IO_22 P0.10 Signal not connected by defualt,
configured for NFC use
8 D7 Digital I/O IO_21 P0.09 Signal not connected by defualt,
configured for NFC use
J4 1 D8 Digital I/O IO_13 P0.14
2 D9 Digital I/O IO_38 P0.24 SWITCH_2 on ANNA-B1.
This signal is pulled low when the
button SW2 is pressed
3 D10 Digital I/O IO_36 P0.22
4 D11 Digital I/O IO_37 P0.23
5 D12 Digital I/O IO_16 P0.18
6 D13 Digital I/O IO_45 P0.20
7 GND Ground GND
8 AREF Analog reference voltage level - - Not connected
9 SDA I2C data signal IO_14 P0.15
10 SCL I2C clock signal IO_15 P0.16
Table 8: Pinout of the Arduino UNO R3 compatible interface
1.7.1 Arduino shield compatibility
The EVK-ANNA-B112 has an I/O voltage range of 1.7-3.6 V. It can therefore be used only with shields
that also support an I/O voltage within this range.
The EVK-ANNA-B112 has a pinout that is compatible with some Arduino or Arduino inspired shields.
This section describes the features of the EVK pins that a shield must comply with:
•IOREF: The I/O voltage level of the ANNA-B112 module is 3.3 V by default, but the EVK can be
modified to allow other voltages (1.7-3.6 V).
•RESET: Is connected to the RESET button (SW0).
•3.3 V: A regulated 3.3 V output. Should not be used as a voltage supply input, use the VIN pin
instead.
•5 V: Is only a 5 V supply output if the EVK is being powered by USB. If any other power
configuration is used, this pin will be unconnected (floating). It is safe to connect an external 5 V
supply to this pin even when a USB cable is connected. This pin cannot be used to power the
board, use the VIN pin instead.
•VIN: May be used as a 5 -12 V supply input to power the EVK-ANNA-B112.
•Pin 0 (RX): Is connected to the ANNA-B112 UART RX pin (ANNA pin 23).
•Pin 1 (TX): Is connected to the ANNA-B112 UART TX pin (ANNA pin 22).

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Note on SCL/SDA: On some Arduino boards, the I2C signals, SCL, and SDA are connected to the pins
A4 and A5 and to the SCL and SDA pins in the top right hand corner. Since these pins will be shorted
together it might cause problems when connected to the EVK-ANNA-B112, which has not shorted
these pins together.
Note on digital I/O pins: Some of the digital I/O pins can be connected to the on-board debug MCU,
thus allowing serial communication and flashing/debugging over USB. This can cause interference
on the signals that are also used by an Arduino shield. See section 1.10 on how to disconnect these
signals from the debug MCU.
1.8 Raspberry Pi compatible interface
The EVK-ANNA-B112 includes a 40-pin IO header that can be used to interface with either a
Raspberry Pi computer board or with a Raspberry Pi expansion board (HAT). The EVK-ANNA-B112
uses different hardware and software configurations depending on if it is connected to a Pi or a HAT;
the differences are covered in this section. The default configuration is to connect to a Pi.
Not all the Raspberry Pi versions and HATs are supported, since it requires the 40-pin IO header,
which older versions did not have. Table 9 lists the compatible Raspberry Pi versions.
Compatible Raspberry Pi boards
Raspberry Pi 1 Model A+
Raspberry Pi 1 Model B+
Raspberry Pi 2 Model B
Raspberry Pi 3 Model B
Raspberry Pi Zero
Raspberry Pi Zero W
Table 9: Compatible Raspberry Pi boards
Figure 14: Pin header J14 that is compatible with the Raspberry Pi IO connectors

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Figure 14 shows the layout of the Raspberry Pi interface and Table 10 explains the pinout in detail.
There are three mounting holes that can be used for increased mechanical stability. The two on
either side of connector J14 are common to all Raspberry Pi boards, but the third one is only
compatible with the Pi Zero boards.
Conn. Pin
No.
Raspberry
Pi pin
Description Schematic
net name
nRF52
pin
Alternate functions and notes
J14 1 3.3 V 3.3 V supply pin 3V3_PI - Not connected by default, see section 1.6
2 5 V 5 V supply pin 5V - Cannot be used as supply input. Supplied
by USB VBUS and protected from back
powering.
3 IO02 Digital I/O IO_14 P0.15
4 5 V 5 V supply pin 5V - Cannot be used as supply input. Supplied
by USB VBUS and protected from back
powering.
5 IO03 Digital I/O IO_15 P0.16
6 GND Ground GND GND
7 IO04 Digital I/O N/C
8 IO14 Digital I/O, UART TX/RX RASP_TXD P0.02 Connected to ANNA UART_RXD pin by
default, see section 1.8.2
9 GND Ground GND GND
10 IO15 Digital I/O, UART RX/TX RASP_RXD P0.03 Connected to ANNA UART_TXD pin by
default, see section 1.8.2
11 IO17 Digital I/O N/C
12 IO18 Digital I/O RESET_N P0.21
13 IO27 Digital I/O IO_13 P0.14
14 GND Ground GND GND
15 IO22 Digital I/O IO_17 Can be connected to IO_17 via zero
Ωresistor. Resistor not mounted by
default. IO_17 is connected to 32.768 LPO
crystal by default
16 IO23 Digital I/O IO_16 P0.18
17 3.3 V 3.3 V supply pin 3V3_PI - Not connected by default, see section 1.6
18 IO24 Digital I/O IO_18
19 IO10 Digital I/O IO_25 P0.31
20 GND Ground GND GND
21 IO09 Digital I/O IO_21 P0.09 Can be connected to IO_21 via zero Ω
resistor. Resistor not mounted by default.
IO_21 is connected to NFC antenna by
default
22 IO25 Digital I/O IO_22 P0.10Can be connected to IO_22 via zero
Ω
resistor. Resistor not mounted by default.
IO_22 is connected to NFC antenna by
default
23 IO11 Digital I/O IO_23 P0.05
24 IO08 Digital I/O IO_24 P0.04
25 GND Ground GND GND
26 IO07 Digital I/O IO_26 P0.30
27 ID_SD EEPROM config I2C data
signal
IO_27 P0.29 Should only be used to read or simulate
HAT EEPROMs, see section 1.8.3
28 ID_SC EEPROM config I2C clock
signal
IO_28 P0.28 Should only be used to read or simulate
HAT EEPROMs, see section 1.8.3
29 IO05 Digital I/O IO_29 P0.27

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Conn. Pin
No.
Raspberry
Pi pin
Description Schematic
net name
nRF52
pin
Alternate functions and notes
30 GND Ground GND GND
31 IO06 Digital I/O IO_31 P0.26
32 IO12 Digital I/O IO_30 P0.25
33 IO13 Digital I/O UART_RTS P0.11
34 GND Ground GND GND
35 IO19 Digital I/O UART_CTS P0.19
36 IO16 Digital I/O IO_36 P0.22
37 IO26 Digital I/O IO_37 P0.23
38 IO20 Digital I/O IO_38 P0.24
39 GND Ground GND GND
40 IO21 Digital I/O IO_45 P0.20
Table 10: Pinout of the Raspberry Pi compatible interface
1.8.1 Powering considerations
There are two voltage nets used in the Raspberry Pi interface 3V3_PI and 5V. Both the 3V3_PI and
5V nets can be used to power HATs, but should not be used when connecting to a Raspberry Pi. See
section 1.6.6 for more information.
⚠The 3V3_PI power net must not be connected to the 3.3 V supply when connected to a Raspberry
Pi board. It could damage both the boards.
1.8.2 UART
The Raspberry Pi interface provides two pins - IO14 and IO15, which can be used for UART
communications. In UART communications, signals are always connected RX <-> TX and vice versa.
This means that on a Raspberry Pi board IO14 will be TX and on a HAT it will be RX. To support talking
to both HATs and Pi boards, the zero Ωresistors - R57, R58, R59 and R60 can be used to toggle the
ANNA TX and RX pins between IO14 and IO15. If an ANNA-B112 is used, this switch can also be made
in the software. By default, the EVK-ANNA-B112 will be configured to simulate a HAT, and IO14 is
connected to the ANNA UART_RXD pin and IO15 is connected to the ANNA UART_TXD pin
respectively.
1.8.3 EEPROM support
The Raspberry Pi interface supports a unique EEPROM solution to store the HAT specific IO
configurations on the HAT board, to be read by the Raspberry Pi before configuring its IOs. The two
pins used for this are ID_SD and ID_SC and are connected to the ANNA-B112 module. The
ANNA-B112 module can thus either read the IO configuration from a HAT, or simulate an EEPROM
and send configurations to a connected Pi. This requires an ANNA-B112 module and a custom built
application.
It is not mandatory to use this EEPROM solution; if not used, the two ANNA pins - IO_42 and IO_41
can be without configurations.
Two pull-up resistors - R44 and R50, can be added to the I2C lines if needed. They are not mounted
on the evaluation board by default.
Visit https://github.com/raspberrypi/hats/blob/master/designguide.md for more information on the
ID EEPROM specification.

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1.9 Buttons and LEDs
Figure 15: Position of the push-buttons and LEDs on the evaluation board
Annotation Function Description
SW0 Reset button Connected directly to the ANNA RESET_N pin.
SW1 User button Push button for application use. Connected directly to the ANNA SWITCH_1
(IO_30) pin
SW2 User button Push button for application use. Connected directly to the ANNA SWITCH_2
(IO_38) pin
Table 11: EVK-ANNA-B112 buttons
Annotation Function Description Color
DS1 UART CTS LED Connected to the ANNA UART_CTS (IO_35) pin via jumper header J9
DS2 UART RTS LED Connected to the ANNA UART_RTS (IO_34) pin via jumper header J9
DS3 Interface MCU LED Blinks on USB enumeration and activity, lit when the Interface MCU is
connected via USB
DS4 Interface MCU LED Error LED
DS5 UART DTR LED Connected to the ANNA UART_DTR (IO_25) pin via jumper header J9
DS6 UART DSR LED Connected to the ANNA UART_DSR (IO_26) pin via jumper header J9
DS7 UART RXD LED Connected to the ANNA UART_RXD (IO_20 pin via jumper header J9
DS8 UART TXD LED Connected to the ANNA UART_TXD (IO_19) pin via jumper header J9
DS9 RGB LED Connected to the ANNA RED (IO_29), GREEN (IO_30) and BLUE (IO_31)
pins via jumper header J19
Table 12: EVK-ANNA-B112 LED indicators
1.10 Disconnecting ANNA signals from board peripherals
All evaluation board peripherals, such as level shifters, LEDs, and the interface MCU will be
connected to the ANNA-B112 module by default. This might not suit all evaluation scenarios. All
peripherals can be switched off by disconnecting their power supplies (see section 1.6), but if only
specific signals have to be isolated, it will require finer control.
All the ANNA module signals that are connected to board peripherals have thus been routed via
jumper headers, so that jumpers can be pulled or added as needed by the evaluation board user,
isolating, or connecting specific signals. Figure 16 shows the layout of these jumper headers.

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Figure 16: Jumper headers J19 and J9 that are used to isolate specific ANNA signals
Connector
annotation
Pin number Schematic net
name
Description
J19 1 RESET_N Reset signal, active low
2 RESET_N_I Connects to the Interface MCU’s reset line
3 SWDIO SWD data signal
4 SWDIO_I Interface MCU SWD data signal, used to program/debug the ANNA
module
5 SWDCLK SWD clock signal
6 SWDCLK_I Interface MCU SWD data signal, used to program/debug the ANNA
module
7 IO_31 ANNA-B112: BLUE signal
8 BLUE RGB diode blue signal, active low
9 IO30/
SWITCH_1
ANNA-B112: SWITCH_1 and GREEN signal
10 GREEN RGB diode green signal, active low
11 IO_29 ANNA-B112: RED signal
12 RED RGB diode red signal, active low
J9 1 IO_25/
UART_DTR
ANNA-B112: UART DTR output
2 UART_DTR_I UART to USB DTR signal
3 IO_26/
UART_DSR
ANNA-B112: UART DSR input
4 UART_DSR_I UART to USB DSR signal
5 IO_34/
UART_RTS
ANNA-B112: UART RTS output
6 UART_RTS_I UART to USB RTS signal
7 IO_35/
UART_CTS
ANNA-B112: UART CTS input
8 UART_CTS_I UART to USB CTS signal
9 IO_19/
UART_TXD
ANNA-B112: UART TXD output
10 UART_TXD_I UART to USB TXD signal
11 IO_20/
UART_RXD
ANNA-B112: UART RXD input

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Connector
annotation
Pin number Schematic net
name
Description
12 UART_RXD_I UART to USB RXD signal
Table 13: Pinout of jumper headers - J19 and J9
1.11 Software debug options
You can debug the software using the following two options in EVK-ANNA-B112:
•Onboard debug solution available on the USB connector
•An external debugger connected to J12 connector
An external debugger connected to the J12 connector is useful when powering the evaluation board
with the CR2032 coin cell battery, or through the external power supply connector J5. It could also
be useful in a scenario where the debug MCU interface has been disconnected from the ANNA-B112
module using the jumpers on J9 header. The SEGGER J-Link software [4] is required to debug using
the onboard J-Link hardware on the EVK-ANNA-B112.

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2Setting up the evaluation board
2.1 Evaluation board setup
The EVK-ANNA-B112 will be delivered with u-blox connectivity software installed.
Before connecting the module, download, and install the latest u-blox s-center evaluation software
from the u-blox website.
To use Bluetooth Low Energy on the EVK-ANNA-B112, connect a 2.4 GHz antenna to the U.FL
antenna connector (J10). The EVK-ANNA-B112C has an onboard antenna.
Plug in either an external power supply in J5 connector or connect to a USB host with a USB cable
attached to J8 connector. You can also power the evaluation board with a CR2032 coin cell battery.
The status light (DS6) will turn green, indicating it has power. The NFC antenna can be connected to
the J11 connector. Both ways of board connection are possible, rotation of 180 degrees.
⚠Be careful to check polarity before connecting an external power supply to the EVK-ANNA-B112
evaluation board. Center conductor is positive (+) and the ring is negative (-).
The very first time you connect the unit to a new computer, drivers need to be installed. The
operating system should handle this automatically.
⚠If the drivers are not installed automatically, download the nRFgo Studio from
www.nordicsemi.com to get the Jlink CDC UART driver.
A COM port will automatically be assigned to the unit by Windows. Do the following to view the
assigned COM ports on Windows 7:
•Open the Control Panel and click Hardware and Sound.
•Click Device Manager in Devices and Printers. This will open Device Manager window where you
can view the assigned COM ports.
2.2 Starting up
2.2.1 EVK-ANNA-B112
Perform the following steps to enable communication with the module:
1. Start the u-blox s-center evaluation software.
2. Use the default baudrate 115200, 8N1 with flow control.
3. You will now be able to communicate with the module through AT commands.
For a list of available AT commands, see the u-blox Short Range AT Commands Manual [3]. To get
started with a basic use case setup of the EVK-ANNA-B112 with u-blox connectivity software, see the
ANNA-B112 Getting Started [5].
2.2.2 EVK-ANNA-B112 SDK
If you would like to use the EVK-ANNA-B112 together with the Nordic Semiconductor SDK, refer to
the Software section of the ANNA-B112 System Integration Manual [2].
2.3 Getting the latest software
Go to the u-blox support webpage to obtain the latest available firmware. Instructions on flashing
the EVK-ANNA-B112 can be found in the Software section of the ANNA-B112 System Integration
Manual [2].