Walter

Board Overview

Walter

Name:

walter

Vendor:

DPTechnics

Architecture:

xtensa

SoC:

esp32s3

Browse board sources

Overview

Walter is a compact IoT development board that combines an Espressif ESP32-S3 SoC with a Sequans Monarch 2 GM02SP LTE-M/NB-IoT/GNSS modem. More information about Walter can be found on the QuickSpot Website [1] and on the QuickSpot GitHub page [2].

Hardware

ESP32-S3-WROOM-1-N16R2 microcontroller:

• Xtensa dual-core 32-bit LX7 CPU

• 16 MiB quad SPI flash memory

• 2 MiB quad SPI PSRAM

• 150 Mbps 802.11 b/g/n Wi-Fi 4 with on-board PCB antenna

• 2 Mbps Bluetooth 5 Low Energy with on-board PCB antenna

Sequans Monarch 2 GM02SP modem:

• Dual-mode LTE-M / NB-IoT (NB1, NB2)

• 3GPP LTE release 14 (Upgradable up to release 17)

• Ultra-low, deep-sleep mode in eDRX and PSM

• Adaptive +23 dBm, +20 dBm and +14 dBm output power

• Integrated LNA and SAW filter for GNSS reception

• Assisted and non-assisted GNSS with GPS and Galileo constellations

• Integrated SIM card

• Nano-SIM card slot

• u.FL RF connectors for GNSS and 5G antennas

Inputs & outputs:

• 24 GPIO pins for application use

• UART, SPI, I²C, CAN, I²S, and SD available on any of the GPIO pins

• ADC, DAC, and PWM integrated in ESP32-S3

• 3.3 V software-controllable output

• USB Type-C connector for flashing and debugging

• 22 test points for production programming and testing

• On-board reset button

Power supply

• 5.0 V via USB Type-C

• 3.0 - 5.5 V via Vin pin

• Not allowed to use both power inputs simultaneously

• Designed for extremely low quiescent current

Form factor

• Easy to integrate via 2.54 mm headers

• 55 mm x 24.8 mm board dimensions

• Pin and footprint compatible with EOL Pycom GPy

• Breadboard friendly

Supported Features

The walter board supports the hardware features listed below.

on-chip / on-board

Feature integrated in the SoC / present on the board.

2 / 2

Number of instances that are enabled / disabled.
Click on the label to see the first instance of this feature in the board/SoC DTS files.

vnd,foo

Compatible string for the Devicetree binding matching the feature.
Click on the link to view the binding documentation.

walter/esp32s3/appcpu target

Type	Location	Description	Compatible
CPU	on-chip	Espressif Xtensa LX7 CPU2	espressif,xtensa-lx7
ADC	on-chip	ESP32 ADC2	espressif,esp32-adc
Bluetooth	on-chip	Bluetooth HCI for Espressif ESP321	espressif,esp32-bt-hci
CAN	on-chip	ESP32 Two-Wire Automotive Interface (TWAI)1	espressif,esp32-twai
Clock control	on-chip	ESP32 RTC (Power & Clock Controller Module) Module1	espressif,esp32-rtc
Counter	on-chip	ESP32 Counter Driver based on RTC Main Timer1	espressif,esp32-rtc-timer
	on-chip	ESP32 general-purpose timers1 3	espressif,esp32-timer
DMA	on-chip	ESP32 GDMA (General Direct Memory Access)1	espressif,esp32-gdma
Flash controller	on-chip	ESP32 flash controller1	espressif,esp32-flash-controller
GPIO & Headers	on-chip	ESP32 GPIO controller2	espressif,esp32-gpio
I2C	on-chip	ESP32 I2C2	espressif,esp32-i2c
I2S	on-chip	ESP32 I2S2	espressif,esp32-i2s
Input	on-chip	ESP32 touch sensor input1	espressif,esp32-touch
Interrupt controller	on-chip	ESP32 Interrupt controller1	espressif,esp32-intc
IPM	on-chip	ESP32 soft inter processor message1	espressif,esp32-ipm
Mailbox	on-chip	ESP32 soft mailbox1	espressif,mbox-esp32
Memory controller	on-chip	ESP32 pseudo-static RAM controller1	espressif,esp32-psram
MTD	on-chip	Flash node1	soc-nv-flash
	on-chip	Fixed partitions of a flash (or other non-volatile storage) memory1	fixed-partitions
Pin control	on-chip	ESP32 pin controller1	espressif,esp32-pinctrl
PWM	on-chip	ESP32 LED Control (LEDC)1	espressif,esp32-ledc
	on-chip	ESP32 Motor Control Pulse Width Modulator (MCPWM)2	espressif,esp32-mcpwm
RNG	on-chip	ESP32 TRNG (True Random Number Generator)1	espressif,esp32-trng
SDHC	on-chip	ESP32 SDHC controller1	espressif,esp32-sdhc
	on-chip	ESP32 SDHC controller slot2	espressif,esp32-sdhc-slot
Sensors	on-chip	ESP32 temperature sensor1	espressif,esp32-temp
	on-chip	ESP32 Pulse Counter (PCNT)1	espressif,esp32-pcnt
Serial controller	on-chip	ESP32 UART3	espressif,esp32-uart
	on-chip	ESP32 UART1	espressif,esp32-usb-serial
SPI	on-chip	ESP32 SPI2	espressif,esp32-spi
SRAM	on-chip	Generic on-chip SRAM description2	mmio-sram
Video	on-chip	ESP32 LCD CAM Peripheral interface1	espressif,esp32-lcd-cam
Watchdog	on-chip	ESP32 XT Watchdog Timer1	espressif,esp32-xt-wdt
	on-chip	ESP32 watchdog2	espressif,esp32-watchdog
Wi-Fi	on-chip	ESP32 SoC Wi-Fi1	espressif,esp32-wifi

walter/esp32s3/procpu target

Type	Location	Description	Compatible
CPU	on-chip	Espressif Xtensa LX7 CPU2	espressif,xtensa-lx7
ADC	on-chip	ESP32 ADC2	espressif,esp32-adc
Bluetooth	on-chip	Bluetooth HCI for Espressif ESP321	espressif,esp32-bt-hci
CAN	on-chip	ESP32 Two-Wire Automotive Interface (TWAI)1	espressif,esp32-twai
Clock control	on-chip	ESP32 RTC (Power & Clock Controller Module) Module1	espressif,esp32-rtc
Counter	on-chip	ESP32 Counter Driver based on RTC Main Timer1	espressif,esp32-rtc-timer
	on-chip	ESP32 general-purpose timers4	espressif,esp32-timer
DMA	on-chip	ESP32 GDMA (General Direct Memory Access)1	espressif,esp32-gdma
Flash controller	on-chip	ESP32 flash controller1	espressif,esp32-flash-controller
GPIO & Headers	on-chip	ESP32 GPIO controller2	espressif,esp32-gpio
I2C	on-chip	ESP32 I2C2	espressif,esp32-i2c
I2S	on-chip	ESP32 I2S2	espressif,esp32-i2s
Input	on-chip	ESP32 touch sensor input1	espressif,esp32-touch
Interrupt controller	on-chip	ESP32 Interrupt controller1	espressif,esp32-intc
IPM	on-chip	ESP32 soft inter processor message1	espressif,esp32-ipm
Mailbox	on-chip	ESP32 soft mailbox1	espressif,mbox-esp32
Memory controller	on-chip	ESP32 pseudo-static RAM controller1	espressif,esp32-psram
Modem	on-board	Sequans Monarch 2 GM02S Modem1	sqn,gm02s
MTD	on-chip	Flash node1	soc-nv-flash
	on-chip	Fixed partitions of a flash (or other non-volatile storage) memory1	fixed-partitions
Pin control	on-chip	ESP32 pin controller1	espressif,esp32-pinctrl
PWM	on-chip	ESP32 LED Control (LEDC)1	espressif,esp32-ledc
	on-chip	ESP32 Motor Control Pulse Width Modulator (MCPWM)2	espressif,esp32-mcpwm
RNG	on-chip	ESP32 TRNG (True Random Number Generator)1	espressif,esp32-trng
SDHC	on-chip	ESP32 SDHC controller1	espressif,esp32-sdhc
	on-chip	ESP32 SDHC controller slot2	espressif,esp32-sdhc-slot
Sensors	on-chip	ESP32 temperature sensor1	espressif,esp32-temp
	on-chip	ESP32 Pulse Counter (PCNT)1	espressif,esp32-pcnt
Serial controller	on-chip	ESP32 UART1 2	espressif,esp32-uart
	on-chip	ESP32 UART1	espressif,esp32-usb-serial
SPI	on-chip	ESP32 SPI2	espressif,esp32-spi
SRAM	on-chip	Generic on-chip SRAM description2	mmio-sram
Video	on-chip	ESP32 LCD CAM Peripheral interface1	espressif,esp32-lcd-cam
Watchdog	on-chip	ESP32 XT Watchdog Timer1	espressif,esp32-xt-wdt
	on-chip	ESP32 watchdog1 1	espressif,esp32-watchdog
Wi-Fi	on-chip	ESP32 SoC Wi-Fi1	espressif,esp32-wifi

Prerequisites

Espressif HAL requires WiFi and Bluetooth binary blobs in order work. Run the command below to retrieve those files.

west blobs fetch hal_espressif

Note

It is recommended running the command above after west update.

Building & Flashing

Simple boot

The board could be loaded using the single binary image, without 2nd stage bootloader. It is the default option when building the application without additional configuration.

Note

Simple boot does not provide any security features nor OTA updates.

MCUboot bootloader

User may choose to use MCUboot bootloader instead. In that case the bootloader must be build (and flash) at least once.

There are two options to be used when building an application:

1. Sysbuild

2. Manual build

Note

User can select the MCUboot bootloader by adding the following line to the board default configuration file.

CONFIG_BOOTLOADER_MCUBOOT=y

Sysbuild

The sysbuild makes possible to build and flash all necessary images needed to bootstrap the board with the ESP32-S3 SoC.

To build the sample application using sysbuild use the command:

west build -b walter/esp32s3/procpu --sysbuild samples/hello_world

By default, the ESP32 sysbuild creates bootloader (MCUboot) and application images. But it can be configured to create other kind of images.

Build directory structure created by sysbuild is different from traditional Zephyr build. Output is structured by the domain subdirectories:

build/
├── hello_world
│   └── zephyr
│       ├── zephyr.elf
│       └── zephyr.bin
├── mcuboot
│    └── zephyr
│       ├── zephyr.elf
│       └── zephyr.bin
└── domains.yaml

Note

With --sysbuild option the bootloader will be re-build and re-flash every time the pristine build is used.

For more information about the system build please read the Sysbuild (System build) documentation.

Manual build

During the development cycle, it is intended to build & flash as quickly possible. For that reason, images can be build one at a time using traditional build.

The instructions following are relevant for both manual build and sysbuild. The only difference is the structure of the build directory.

Note

Remember that bootloader (MCUboot) needs to be flash at least once.

Build and flash applications as usual (see Building an Application and Run an Application for more details).

# From the root of the zephyr repository
west build -b walter/esp32s3/procpu samples/hello_world

The usual flash target will work with the walter board configuration. Here is an example for the Hello World application.

# From the root of the zephyr repository
west build -b walter/esp32s3/procpu samples/hello_world
west flash

Open the serial monitor using the following command:

west espressif monitor

After the board has automatically reset and booted, you should see the following message in the monitor:

***** Booting Zephyr OS vx.x.x-xxx-gxxxxxxxxxxxx *****
Hello World! walter/esp32s3/procpu

Debugging

ESP32-S3 support on OpenOCD is available at OpenOCD ESP32 [4].

ESP32-S3 has a built-in JTAG circuitry and can be debugged without any additional chip. Only an USB cable connected to the D+/D- pins is necessary.

Further documentation can be obtained from the SoC vendor in JTAG debugging for ESP32-S3 [3].

Here is an example for building the Hello World application.

# From the root of the zephyr repository
west build -b walter/esp32s3/procpu samples/hello_world
west flash

You can debug an application in the usual way. Here is an example for the Hello World application.

# From the root of the zephyr repository
west build -b walter/esp32s3/procpu samples/hello_world
west debug

References

[1]

https://www.quickspot.io/

[2]

https://github.com/QuickSpot

[3]

https://docs.espressif.com/projects/esp-idf/en/latest/esp32s3/api-guides/jtag-debugging/

[4]

https://github.com/openocd-org/openocd