ESP32 NanoView

Reads data from a NanoView and sends it as JSON via MQTT.
Intended to be useful with Grafana + InfluxDB or similar.

Wiring

Useful info can be found at: Hacking the NanoView with a RPi Zero W.
Instead of connecting TX to the RPi via voltage divider (Step 8 in the article linked above), connect it to the ESP32 configured UART RX pin (GPIO 5 as set in nanoview_uart.c). Ensure the ground of NanoHub and ESP32 are connected together too.

ESP32 esp-idf Project Configuration

Menuconfig

Either run idf.py menuconfig and set the WiFi and MQTT parameters (under "MQTT and WiFi Configuration"), or use an include file as below.

Include File

Create nanoview_config.h in the main/ directory, and enable the Use nanoview_config.h instead of below configuration option from idf.py menuconfig

The file content should be as below:

#define ESP_WIFI_SSID      "your_wifi_name"
#define ESP_WIFI_PASS      "your_super_secret_wifi_key"
#define ESP_MAXIMUM_RETRY  10

#define BROKER_URL "mqtt://esp32-nanoview:yourpassword@192.168.0.123"

MQTT Setup

Install an MQTT broker (eg: Mosquitto), and create /etc/mosquitto/mosquitto.conf with the below or similar.

log_dest syslog
connection_messages true
password_file /etc/mosquitto/pwfile

Update/create your password_file (/etc/mosquitto/pwfile), eg: mosquitto_passwd [-c] esp32-nanoview

Note: -c will create/overwrite existing files.

Telegraf Setup

Telegraf can ingest JSON from the MQTT broker, and store data in InfluxDB. An example configuration is below. InfluxDB v1.x is recommended for now.

Example /etc/telegraf/telegraf.conf below:

# Below are just the defaults, whatever your distribution sets is probably fine. You likely just need to set up the outputs and inputs sections.
[global_tags]
[agent]
  interval = "10s"
  round_interval = true
  metric_batch_size = 1000
  metric_buffer_limit = 10000
  collection_jitter = "0s"
  flush_interval = "10s"
  flush_jitter = "0s"
  precision = ""
  hostname = ""
  omit_hostname = false

# Recommend using InfluDB v1.x to be able to use the included Grafana queries/dashboard examples.
[[outputs.influxdb]]
  urls = ["http://127.0.0.1:8086"]
   database = "telegraf"

# But you can output to InfluxDB v2 just fine too if you wish
[[outputs.influxdb_v2]]
  urls = ["http://localhost:9999"]
  token = "your_influx_v2_token"
  organization = "your_org"
  bucket = "your_bucket"

# Consume the JSON from your MQTT broker
[[inputs.mqtt_consumer]]
  servers = ["tcp://esp32-nanoview:your_mqtt_password@192.168.0.123:1883"]
  topics = [
    "/esp-mqtt/nanoview"
  ]
  data_format = "json"
  json_name_key = "name"
  tag_keys = ["channel"]

Grafana Setup

Install Grafana and add your InfluxDB v1.x datasource. To import the included dashboard, configure the datasource as:

Name: InfluxDB1
Query Language: InfluxQL
Database: telegraf (or whatever you set in your telegraf.conf)

Import the included grafana/grafana-example.json dashboard (Dashboards -> Manage -> Import) to get something like the below. Select your Influx v1.x datasource and set a name as desired. You'll likely need to update the annotations and field overrides for your own setup.

denvera / esp32-nanoview