golioth-serial-logger

This firmware enables remote logging of serial data from a target device to the Golioth logging service via a WiFi connection.

┌──────────┐                  ┌──────────┐             ┌──────────────┐
│          │                  │          │             │              │
│  Target  │─────UART TX─────▶│  Serial  │     WiFi    │   Golioth    │
│  Device  │◀────UART RX──────│  Logger  │◀ ─ ─ ─ ─ ─ ▶│    Cloud     │
│          │                  │          │             │              │
└──────────┘                  └──────────┘             └──────────────┘

Note

This is currently a very rough proof-of-concept and should not be used in production.

Hardware Setup

The serial logger firmware currently supports the following devices:

ESP32-C3-DevKitM-1

Connect the target device's UART pins to the ESP32-C3-DevKitM-1 pins as follows:

Target device UART ESP32-C3-DevKitM-1 UART

GND GND

RXD GPIO7

TXD GPIO6
Connect the ESP32-C3-DevKitM-1 USB port to your PC (this is only needed to configure the device).

Target device UART	ESP32-C3-DevKitM-1 UART
`GND`	`GND`
`RXD`	`GPIO7`
`TXD`	`GPIO6`

Firmware Setup

Set up a build environment

mkdir golioth-serial-logger-workspace
cd golioth-serial-logger-workspace
python -m venv .venv
source .venv/bin/activate
pip install -U pip wheel west
west init -m git@github.com:cgnd/golioth-serial-logger .
cd golioth-serial-logger/
west update
west zephyr-export
pip install -r ../zephyr/scripts/requirements.txt
west blobs fetch hal_espressif

Build the firmware

west build -p -b esp32c3_devkitm --sysbuild app

Flash the firmware

west flash --esp-device=/dev/<your_serial_port>

Configure the logger to connect to Golioth

Open a serial terminal connection to the USB-serial port on the ESP32-C3-DevKitM-1 (115200 baud 8-N-1).

Note

The instructions below assume that you've already provisioned the device in the Golioth console to use Pre-Shared Key (PSK) authentication.

In the Zephyr shell, configure the serial logger device settings as follows:

settings set wifi/ssid "<YOUR WIFI SSID>"
settings set wifi/psk "<YOUR WIFI PASSWORD>"
settings set golioth/psk-id <GOLIOTH-PSK-ID>
settings set golioth/psk <GOLIOTH-PSK>

Reboot the logger device:

kernel reboot cold

Wait for the logger device to connect to Golioth:

*** Booting Zephyr OS build v3.6.0 ***
[00:00:00.176,000] <inf> fs_nvs: 6 Sectors of 4096 bytes
[00:00:00.176,000] <inf> fs_nvs: alloc wra: 0, f88
[00:00:00.176,000] <inf> fs_nvs: data wra: 0, 94
[00:00:00.178,000] <inf> main: Starting Golioth Serial Logger App
[00:00:00.178,000] <inf> golioth_samples: Bringing up network interface
[00:00:00.178,000] <inf> golioth_samples: Waiting to obtain IP address
[00:00:00.178,000] <inf> golioth_wifi: Connecting to 'Wilson'
[00:00:05.134,000] <inf> net_dhcpv4: Received: 192.168.1.165
[00:00:05.135,000] <inf> golioth_mbox: Mbox created, bufsize: 1320, num_items: 10, item_size: 120
[00:00:05.584,000] <inf> golioth_coap_client_zephyr: Golioth CoAP client connected
[00:00:05.584,000] <inf> main: Golioth client connected
[00:00:05.584,000] <inf> golioth_coap_client_zephyr: Entering CoAP I/O loop

At this point, the logging device is ready for the target to start sending UART data.

Usage

Each line of UART data sent by the target device will be automatically sent to the Golioth logging service when a \n or \r is received from the target device.

Since this is currently just a quick proof-of-concept, there are a bunch of limitations:

The UART connection between the target and the serial logger is hard coded to 115200 baud 8-N-1.
Log messages from the target must be less than 256 bytes long.
The connection to Golioth requires Pre-Shared Key (PSK) authentication.

ayavilevich/golioth-serial-logger