u-blox EVK-BMD-34/38: BMD-345-EVAL

Overview

The BMD-345-EVALhardware provides support for the u-blox BMD-345 Bluetooth 5.0 modules, based on the Nordic Semiconductor nRF52840 ARM Cortex-M4F CPU and Skyworks RFX2411 Front End Module (FEM), also known as a Power Amplifier / Low Noise Amplifier (PA/LNA). Both support the following devices:

  • ADC

  • CLOCK

  • FLASH

  • GPIO

  • I2C

  • MPU

  • NVIC

  • PWM

  • RADIO (Bluetooth Low Energy and 802.15.4)

  • RTC

  • Segger RTT (RTT Console)

  • SPI

  • UART

  • USB

  • WDT

BMD 345 EVAL

BMD-345-EVAL (Credit: ublox AG)

More information about the BMD-345-EVAL and BMD-345 module can be found at the u-blox website [1].

Hardware

The BMD-345 on the BMD-345-EVAL contains an internal high-frequency oscillator at 32MHz. There is also a low frequency (slow) oscillator of 32.768kHz. The BMD-345 does not include the slow crystal; however, the BMD-345-EVAL does.

Note

When targeting a custom design without a slow crystal, be sure to modify code to utilize the internal RC oscillator for the slow clock.

Front End Module

BMD-345 utilizes the Skyworks RFX2411 front end module (FEM). The FEM provides higher output power and better sensitivity.

FEM pin assignments

GPIO Number

Signal Name

Shutdown

Bypass

Transmit

Receive

P1.05

TX_EN

Low

Low

High

Low

P1.06

RX_EN

Low

Low

Low

High

P1.04

MODE

Low

High

Low

Low

P1.02

A_SEL

Low

Low

Low

Low

Supported Features

The BMD-345-EVAL board configuration supports the following hardware features:

Interface

Controller

Driver/Component

ADC

on-chip

adc

CLOCK

on-chip

clock_control

FLASH

on-chip

flash

GPIO

on-chip

gpio

I2C(M)

on-chip

i2c

MPU

on-chip

arch/arm

NVIC

on-chip

arch/arm

PWM

on-chip

pwm

RADIO

on-chip

Bluetooth, IEEE 802.15.4

RTC

on-chip

system clock

RTT

Segger

console

SPI(M/S)

on-chip

spi

UART

on-chip

serial

USB

on-chip

usb

WDT

on-chip

watchdog

Other hardware features have not been enabled yet for this board. See the u-blox website [1] for a complete list of BMD-345-EVAL hardware features.

Connections and IOs

LED

  • LED1 (red) = P0.13

  • LED2 (red) = P0.14

  • LED3 (green) = P0.15

  • LED4 (green) = P0.16

  • D5 (red) = OB LED 1

  • D6 (green) = OB LED 2

Push buttons

  • BUTTON1 = SW1 = P0.11

  • BUTTON2 = SW2 = P0.12

  • BUTTON3 = SW3 = P0.24

  • BUTTON4 = SW4 = P0.25

  • BOOT = SW5 = boot/reset

External Connectors

BMD-345-EVAL pin-out

Note

The pin numbers noted below are referenced to the pin 1 markings on the BMD-340-EVAL or BMD-341-EVAL for each header

J-Link Prog Connector (J2)

PIN #

Signal Name

1

VDD

2

IMCU_TMSS

3

GND

4

IMCU_TCKS

5

V5V

6

IMCU_TDOS

7

Cut off

8

IMCU_TDIS

9

Cut off

10

IMCU_RESET

Debug OUT (J3)

PIN #

Signal Name

1

EXT_VTG

2

EXT_SWDIO

3

GND

4

EXT_SWDCLK

5

GND

6

EXT_SWO

7

N/C

8

N/C

9

EXT_GND_DETECT

10

EXT_RESET

Debug IN (J26)

PIN #

Signal Name

1

BMD-340_VCC

2

BMD-340_SWDIO

3

GND

4

BMD-340_SWDCLK

5

GND

6

BMD-340_SWO

7

N/C

8

N/C

9

GND

10

BMD-340_RESET

Auxiliary (J9)

PIN #

Signal Name

1

P0.10 / NFC2

2

P0.09 / NFC1

3

P0.08

4

P0.07

5

P0.06

6

P0.05 / AIN3

7

P0.01 / XL2

8

P0.00 / XL1

Auxiliary (J10)

PIN #

Signal Name

1

P0.11 / TRACED[2]

2

P0.12 / TRACED[1]

3

P0.13

4

P0.14

5

P0.15

6

P0.16

7

P0.17 / QSPI_CS

8

P0.18 / RESET

9

P0.19 / QSPI_CLK

10

P0.20 / QSPI_D0

11

P0.21 / QSPI_D1

12

P0.22 / QSPI_D2

13

P0.23 / QSPI_D3

14

P0.24

15

P0.25

16

P1.00 / TRACED[0]

17

P1.09 / TRACED[3]

18

No connection

Arduino Headers

Power (J5)

PIN #

Signal Name

BMD-345 Functions

1

VSHLD

N/A

2

VSHLD

N/A

3

RESET

P0.18 / RESET

4

VSHLD

N/A

5

V5V

N/A

6

GND

N/A

7

GND

N/A

8

N/C

N/A

Analog in (J8)

PIN #

Signal Name

BMD-345 Functions

1

A0

P0.03 / AIN1

2

A1

P0.04 / AIN2

3

A2

P0.28 / AIN4

4

A3

P0.29 / AIN5

5

A4

P0.30 / AIN6

6

A5

P0.31 / AIN7

Digital I/O (J7)

PIN #

Signal Name

BMD-345 Functions

1

D7

P1.08

2

D6

P1.07

3

N/C

N/A

4

N/C

N/A

5

N/C

N/A

6

D2

P1.03

7

N/C

N/A

8

D0 (RX)

P1.01

Digital I/O (J6)

PIN #

Signal Name

BMD-345 Functions

1

SCL

P0.27

2

SDA

P0.26

3

AREF

P0.02 / AIN0

4

GND

N/A

5

D13 (SCK)

P1.15

6

D12 (MISO)

P1.14

7

D11 (MOSI)

P1.13

8

D10 (SS)

P1.12

9

D9

P1.11

10

D8

P1.10

J11

PIN #

Signal Name

BMD-345 Functions

1

D12 (MISO)

P0.14

2

V5V

N/A

3

D13 (SCK)

P0.15

4

D11 (MOSI)

P0.13

5

RESET

N/A

6

N/A

N/A

Programming and Debugging

Applications for the BMD-345-EVAL board configurations can be built and flashed in the usual way (see Building an Application and Run an Application for more details); however, the standard debugging targets are not currently available.

Flashing

Follow the instructions in the Nordic nRF5x Segger J-Link page to install and configure all the necessary software. Further information can be found in Flashing. Then build and flash applications as usual (see Building an Application and Run an Application for more details).

Here is an example for the Hello World application.

First, run your favorite terminal program to listen for output.

$ minicom -D <tty_device> -b 115200

Replace <tty_device> with the port where the BMD-345-EVAL can be found. For example, under Linux, /dev/ttyACM0.

Then build and flash the application in the usual way.

# From the root of the zephyr repository
west build -b ubx_bmd345eval_nrf52840 samples/hello_world
west flash

Debugging

Refer to the Nordic nRF5x Segger J-Link page to learn about debugging u-blox boards with a Segger J-LINK-OB IC.

Testing the LEDs and buttons in the BMD-345-EVAL

There are 2 samples that allow you to test that the buttons (switches) and LEDs on the board are working properly with Zephyr:

samples/basic/blinky
samples/basic/button

You can build and flash the examples to make sure Zephyr is running correctly on your board. The button and LED definitions can be found in boards/arm/ubx_bmd340eval_nrf52840/ubx_bmd345eval_nrf52840.dts.

Using UART1

The following approach can be used when an application needs to use more than one UART for connecting peripheral devices:

  1. Add device tree overlay file to the main directory of your application:

    &pinctrl {
   uart1_default: uart1_default {
      group1 {
         psels = <NRF_PSEL(UART_TX, 0, 14)>,
                 <NRF_PSEL(UART_RX, 0, 16)>;
      };
   };
   /* required if CONFIG_PM_DEVICE=y */
   uart1_sleep: uart1_sleep {
      group1 {
         psels = <NRF_PSEL(UART_TX, 0, 14)>,
                 <NRF_PSEL(UART_RX, 0, 16)>;
         low-power-enable;
      };
   };
};

&uart1 {
  compatible = "nordic,nrf-uarte";
  current-speed = <115200>;
  status = "okay";
  pinctrl-0 = <&uart1_default>;
  pinctrl-1 = <&uart1_sleep>;
  pinctrl-names = "default", "sleep";
};

    In the overlay file above, pin P0.16 is used for RX and P0.14 is used for TX

  2. Use the UART1 as DEVICE_DT_GET(DT_NODELABEL(uart1))

Overlay file naming

The file has to be named <board>.overlay and placed in the app main directory to be picked up automatically by the device tree compiler.

Selecting the pins

Pins can be configured in the board pinctrl file. To see the available mappings, open the data sheet for the BMD-345 at the u-blox website [1], Section 2 ‘Pin definition’. In the table 3 select the pins marked ‘GPIO’. Note that pins marked as ‘Standard drive, low frequency I/O only (<10 kH’ can only be used in under-10KHz applications. They are not suitable for 115200 speed of UART.

References