Thingy:52

Overview

Zephyr uses the thingy52_nrf52832 (PCA20020) board configuration for building for the Thingy:52 board. The board has the nRF52832 MCU with ARM Cortex-M4F processor, a set of environmental sensors, a pushbutton, and two RGB LEDs.

  • ADC

  • CLOCK

  • FLASH

  • Gas sensor

  • GPIO

  • GPIO Expander

  • Humidity and temperature sensor

  • I2C

  • MPU

  • NVIC

  • Pressure sensor

  • PWM

  • RADIO (Bluetooth Low Energy)

  • RGB LEDs

  • RTC

  • SPI

  • UART

  • WDT

nRF52 Thingy:52

nRF52 Thingy:52 (Credit: Nordic Semiconductor)

More information about the board can be found at the nRF52 DK website 1. The Nordic Semiconductor Infocenter 2 contains the processor’s information and the datasheet.

Hardware

Thingy:52 has the following features:

  • Two RGB LEDs

  • CO2 and TVOC sensor

  • Humidity and temperature sensor

  • Color sensor

  • I2C GPIO expander

  • Provisions for a pin header and I2C and serial connectors

  • Bluetooth radio

Supported Features

Interface

Controller

Driver/Component

ADC

on-chip

adc

CLOCK

on-chip

clock_control

FLASH

on-chip

flash

Gas Sensor

on-board

ccs811

GPIO

on-chip

gpio

GPIO Exp

on-board

sx1509b

Humidity and Temp

on-board

hts221

I2C(M)

on-chip

i2c

MPU

on-chip

arch/arm

NVIC

on-chip

arch/arm

Pressure and Temp

on-board

lps22hb_press

PWM

on-chip

pwm

RADIO

on-chip

Bluetooth

RTC

on-chip

system clock

SPI(M/S)

on-chip

spi

UART

on-chip

serial

WDT

on-chip

watchdog

Connections and IOs

Lightwell RGB LED

The LED is driven by the SX1509B GPIO expander chip (device name GPIO_P0).

GPIO Expander Pin

LED Channel

5

Green

6

Blue

7

Red

Button

Thingy:52 has a pushbutton, connected to the P0.11 SOC GPIO pin.

Serial

By default the system UART has the following pin configuration:

SOC Pin

Signal

P0.02

TX

P0.03

RX

The pins can be found on the P4 and P6 connectors. The system UART console uses these pins by default.

Internal I2C Bus

The internal I2C bus (I2C_0) is not routed to any of the external connectors, but most of the on-board devices are accessed through it. The following pins have been assigned to the bus:

SOC Pin

Signal

P0.07

SDA

P0.08

SCL

The following devices are attached to the bus.

Device

Address

SX1509B

0x3e

LPS22HB

0x5c

HTS221

0x5f

CCS811

0x5a

External I2C Bus

The external I2C bus (I2C_1) can be found on the P4 header and the P5 and P7 connectors.

SOC Pin

Signal

P0.14

SDA_EXT

P0.15

SCL_EXT

Pin Header

This is the pinout of the P4 pin header. Some of the SOC GPIO pins and I2C GPIO expander pins are accessible through it. It also allows attaching external devices to the four on-board N-channel MOSFET transistors.

Pin

Device

Signal / Device Pin

1

SOC

SCL_EXT / P0.15

2

SOC

SDA_EXT / P0.14

3

SOC

ANA/DIG0 / P0.02

4

SOC

ANA/DIG1 / P0.03

5

SOC

ANA/DIG2 / P0.04

6

GND

7

GPIO Expander

Pin 0

8

GPIO Expander

Pin 1

9

GPIO Expander

Pin 2

10

GPIO Expander

Pin 3

11

MOSFET 1

Drain

12

MOSFET 1

Source

13

MOSFET 2

Drain

14

MOSFET 2

Source

15

MOSFET 3

Drain

16

MOSFET 3

Source

17

MOSFET 4

Drain

18

MOSFET 4

Source

19

VDD

20

GND
MOSFETs

The MOSFETs are attached to the following SOC GPIO pins:

Device

Gate Pin

MOSFET 1

P0.18

MOSFET 2

P0.19

MOSFET 3

P0.20

MOSFET 4

P0.21

Power Rails

Thing:52 has multiple power rails. The necessary rails for the currently supported devices are listed here.

Name

Derived from

Controlled by

VREG

The battery

Always on

VDD_nRF

VREG

Always on

VDD

VREG

SOC pin P0.30

VDD_CCS

VDD

GPIO expander pin 10

Due to the dependencies of the power rails, multiple rails may need to be powered for a given device to turn on. The correct order of powering up the rails is the order of the rails down the dependency chain. For example, in order to power the CCS811 gas sensor, VDD has to be turned on first and VDD_CCS after it. Here’s a list of the devices and their power rails:

Device

Rail

nRF52832

VDD_nRF

SX1509B

VDD

LPS22HB

VDD

HTS221

VDD

CCS811

VDD_CCS

Sensors

Device

Function

Bus

I2C Address

Power Rail

LPS22HB

Pressure and Temperature sensor

I2C_0

0x5c

VDD

HTS221

Humidity and Temperature sensor

I2C_0

0x5f

VDD

CCS811

Gas sensor

I2C_0

0x5a

VDD_CCS

Misc. Device Pins

SX1509B

Device Signal

SOC Pin

SX_OSCIO

P0.05

SX_RESET

P0.16
LPS22HB

Sensor Signal

SOC Pin

LPS_INT

P0.23
HTS221

Sensor Signal

SOC Pin

HTS_INT

P0.24
CCS811

Sensor Signal

GPIO Expander Pin

CCS_RESET

11

CCS_WAKE

12

Programming and Debugging

Flashing

Flashing Zephyr onto Thingy:52 requires an external J-Link programmer. The programmer is attached to the P9 programming header.

Debugging

Thingy:52 does not have an on-board J-Link debug IC as some other nRF5 development boards, however, instructions from the Nordic nRF5x Segger J-Link page also apply to this board, with the additional step of connecting an external debugger. A development board with a Debug out connector such as the nRF52 DK can be used as a debugger with Thingy:52.

Testing board features

The green lightwell LED can be tested with the Blinky example.

# From the root of the zephyr repository
west build -b thingy52_nrf52832 samples/basic/blinky
west flash

Also the temperature and humidity sensor can be tested with the HTS221: Temperature and Humidity Monitor sample.

# From the root of the zephyr repository
west build -b thingy52_nrf52832 samples/sensor/hts221
west flash