@ya-modbus/driver-xymd1

XYMD1 Temperature and Humidity Sensor driver for ya-modbus.

Device Information

• Model: XY-MD1
• Type: Temperature and Humidity Sensor
• Communication: Modbus RTU
• Default Settings:
  • Address: 1
  • Baud rate: 9600
  • Parity: Even
  • Stop bits: 1
  • Data bits: 8

Installation

npm install @ya-modbus/driver-xymd1

Usage

import { createDriver } from '@ya-modbus/driver-xymd1'
import { ModbusRTU } from '@ya-modbus/transport-rtu'

// Create transport
const transport = new ModbusRTU({
  path: '/dev/ttyUSB0',
  baudRate: 9600,
  parity: 'even',
})

// Create driver
const driver = await createDriver({
  transport,
  slaveId: 1,
})

// Read temperature and humidity
const values = await driver.readDataPoints(['temperature', 'humidity'])
console.log(values)
// { temperature: 24.5, humidity: 65.2 }

// Read current device configuration
const currentAddress = await driver.readDataPoint('device_address')
const currentBaudRate = await driver.readDataPoint('baud_rate')
console.log(`Current config: address=${currentAddress}, baudRate=${currentBaudRate}`)

// Configure device address (requires device restart to take effect)
await driver.writeDataPoint('device_address', 5)

// Configure baud rate (requires device restart to take effect)
await driver.writeDataPoint('baud_rate', 19200)

// Calibrate sensor (applied immediately)
await driver.writeDataPoint('temperature_correction', -1.5)
await driver.writeDataPoint('humidity_correction', 2.0)

Using Default Configuration

The driver exports a DEFAULT_CONFIG constant with factory-default device settings:

import { createDriver, DEFAULT_CONFIG } from '@ya-modbus/driver-xymd1'
import { ModbusRTU } from '@ya-modbus/transport-rtu'

// Use default configuration for connecting to factory-default device
const transport = new ModbusRTU({
  path: '/dev/ttyUSB0',
  baudRate: DEFAULT_CONFIG.baudRate, // 9600
  parity: DEFAULT_CONFIG.parity, // 'even'
  dataBits: DEFAULT_CONFIG.dataBits, // 8
  stopBits: DEFAULT_CONFIG.stopBits, // 1
})

const driver = await createDriver({
  transport,
  slaveId: DEFAULT_CONFIG.defaultAddress, // 1
})

This ensures your code always uses the correct factory defaults and makes it easier to update if device specifications change.

Data Points

| ID | Name | Type | Unit | Access | Description | | ------------------------ | ---------------------- | ------- | ---- | ---------- | ------------------------------------------------------------------------------------------ | | temperature | Temperature | float | °C | Read-only | Temperature in degrees Celsius | | humidity | Relative Humidity | float | % | Read-only | Relative humidity percentage (0-100%) | | device_address | Device Address | integer | - | Read-write | Modbus device address (1-247). Changes applied after device restart. | | baud_rate | Baud Rate | enum | - | Read-write | Serial communication baud rate (9600, 14400, 19200). Changes applied after device restart. | | temperature_correction | Temperature Correction | float | °C | Read-write | Temperature correction offset (-10.0 to +10.0°C). Applied immediately. | | humidity_correction | Humidity Correction | float | % | Read-write | Humidity correction offset (-10.0 to +10.0%RH). Applied immediately. |

Register Mapping

| Function | Register | Type | Format | Description | | ------------- | -------- | ------- | --------------- | ------------------------------------------ | | Read | 1-2 | Input | 16-bit × 2 | Temperature and humidity (×10) | | Configuration | 0x101 | Holding | 16-bit unsigned | Device address (1-247) | | Configuration | 0x102 | Holding | 16-bit unsigned | Baud rate setting | | Calibration | 0x103 | Holding | 16-bit signed | Temperature correction (×10, -100 to +100) | | Calibration | 0x104 | Holding | 16-bit signed | Humidity correction (×10, -100 to +100) |

Calibration

The XYMD01 supports temperature and humidity correction to calibrate sensor readings against reference measurements.

Using the Driver API

// Example: Calibrate temperature
// 1. Measure actual temperature with reference device: 23.0°C
// 2. Read XYMD01 sensor: 25.5°C
// 3. Calculate correction: 23.0 - 25.5 = -2.5°C

await driver.writeDataPoint('temperature_correction', -2.5)

// Verify corrected reading
const temp = await driver.readDataPoint('temperature')
// temp should now be approximately 23.0°C

// Example: Calibrate humidity
await driver.writeDataPoint('humidity_correction', 1.5)

Using the CLI

# Set temperature correction
ya-modbus write \
  --port /dev/ttyUSB0 \
  --slave-id 1 \
  --data-point temperature_correction \
  --value -2.5 \
  --yes \
  --verify

# Set humidity correction
ya-modbus write \
  --port /dev/ttyUSB0 \
  --slave-id 1 \
  --data-point humidity_correction \
  --value 1.5 \
  --yes \
  --verify

# Read all values including corrections
ya-modbus read \
  --port /dev/ttyUSB0 \
  --slave-id 1 \
  --all

Notes

• Corrections are applied immediately (no device restart required)
• Values are stored in device holding registers and persist across power cycles
• Correction range: -10.0 to +10.0 for both temperature (°C) and humidity (%RH)
• The corrected values are reflected in the temperature and humidity input registers

License

GPL-3.0-or-later