CHESTER Range

This article describes the core functionality, hardware description, and example JSON message of the catalog application CHESTER Range.

caution

Some of the basics are not provided, as they are common for all CHESTER catalog applications. Please see:

• Getting started on how to connect device to Cloud.
• Common functionality to know how LED, button and network configuration works.
• Platform Management on how to work with the interactive console.

Application Overview

CHESTER Range measures distance using the MaxBotix MB7066 ultrasonic sensor. It can also measure temperature using the DS18B20 one-wire sensor and humidity using CHESTER-S2.

Application Variants

CHESTER Range can be ordered in one of these variants:

CHESTER Range

The catalog CHESTER Range hardware consists of the following ordering codes:

• CHESTER-M-CGLS - Standard mainboard

• CHESTER-X0A:A - Input module (4 channels)

See Ordering Codes for more details.

Firmware build shield options: ctr_lte ctr_mb7066_a

CHESTER Range Z

The catalog CHESTER Range Z hardware consists of the following ordering codes:

• CHESTER-M-CGLS - Standard mainboard

• CHESTER-X0A:A - Input module (4 channels)

• CHESTER-Z1 - Backup module

See Ordering Codes for more details.

Firmware build shield options: ctr_lte ctr_mb7066_a ctr_z

Measurement and Behavior

• All sensors are sampled with a configurable period (parameter interval-sample).
• Samples are then aggregated in the configurable interval. Minimum, maximum, average, and median are computed from buffered samples for each sensor (parameter interval-aggreg).
• Each aggregated values have its timestamps and are sent in a batch in a report interval period (parameter interval-report).

Terminal Blocks

Connect the sensor to the left terminal block A

CHESTER-X0 in left slot A	Maxbotix cable color	Signal
A2 (CH1)	red	Power
A3 (GND)	black	GND
A4 (CH2)	yellow	Pulse

Default Configuration

This is the default configuration (printed using the app config show command):

app config interval-sample 60
app config interval-aggreg 300
app config interval-report 1800

Specific Commands

info

You can easily explore the whole command tree structure - start with the help command.

caution

To apply a new configuration, you need to call config save, which applies the new configuration parameters and reboots the device.

Command to set sample interval in seconds:

app config interval-sample <1-86400>

Command to set aggregate interval in seconds:

app config interval-aggreg <1-86400>

Command to set report interval in seconds:

app config interval-report <30-86400>

aggreg

Firmware

The latest firmware is available in Catalog Applications Firmware chapter.

Example JSON Message

In this example JSON you can see data from all three variants

Every available sensor has one aggrevated measurement, which contains the minimum, maximum, average and median value.

{
  "message": {
    "version": 1,
    "sequence": 1,
    "timestamp": 1685093572
  },
  "attribute": {
    "vendor_name": "HARDWARIO",
    "product_name": "CHESTER-M",
    "hw_variant": "CDGLS",
    "hw_revision": "R3.4",
    "fw_name": "(unset)",
    "fw_version": "(unset)",
    "serial_number": "2159019054"
  },
  "system": {
    "uptime": 49,
    "voltage_rest": null,
    "voltage_load": null,
    "current_load": null
  },
  "network": {
    "imei": 351358816140765,
    "imsi": 901288910018953,
    "parameter": {
      "eest": 7,
      "ecl": 0,
      "rsrp": -78,
      "rsrq": -5,
      "snr": 8,
      "plmn": 23003,
      "cid": 1011233,
      "band": 20,
      "earfcn": 6447
    }
  },
  "thermometer": {
    "temperature": 24.93
  },
  "accelerometer": {
    "acceleration_x": 0,
    "acceleration_y": -0.23,
    "acceleration_z": 9.65,
    "orientation": 2
  },
  "ultrasonic_ranger": {
    "distance": {
      "measurements": [
        {
          "timestamp": 1685093569,
          "min": 2.004,
          "max": 2.009,
          "avg": 2.008,
          "mdn": 2.008
        }
      ]
    }
  },
  "hygrometer": {
    "temperature": {
      "events": [],
      "measurements": [
        {
          "timestamp": 1685093569,
          "min": 24.9,
          "max": 25.03,
          "avg": 24.99,
          "mdn": 25.01
        }
      ]
    },
    "humidity": {
      "measurements": [
        {
          "timestamp": 1685093569,
          "min": 35.18,
          "max": 35.81,
          "avg": 35.45,
          "mdn": 35.36
        }
      ]
    }
  },
  "w1_thermometers": [
    {
      "serial_number": 222768959,
      "measurements": [
        {
          "timestamp": 1685093569,
          "min": 24.31,
          "max": 24.31,
          "avg": 24.31,
          "mdn": 24.31
        }
      ]
    },
    {
      "serial_number": 222690915,
      "measurements": [
        {
          "timestamp": 1685093569,
          "min": 27,
          "max": 27.43,
          "avg": 27.22,
          "mdn": 27.25
        }
      ]
    }
  ]
}