Remote Voltmeter - TypeScript SCPI Library

Professional TypeScript library for working with the GW Instek GDM-9061 digital multimeter using SCPI protocol (Standard Commands for Programmable Instruments) through network connection.

📋 Features

• ✅ Full SCPI command support for GW Instek GDM-9061
• ✅ TCP/IP connection support (RS232 through network gateway)
• ✅ Complete TypeScript typing (types and interfaces)
• ✅ Asynchronous API with Promise
• ✅ Error handling and timeouts
• ✅ Automatic reconnection
• ✅ Events (connected, disconnected, error, timeout)
• ✅ Support for multiple measurement modes
• ✅ Trigger and display control

� Documentation

• Quick Start Guide - Get started quickly with basic usage
• Project Summary - Detailed project overview and architecture
• Integration Guide - Advanced integration examples and API reference

�📦 Installation

npm install

🏗️ Build

npm run build

📖 Usage

📟 Command-line Interface

A small CLI is provided with the package after installation. It wraps the primary driver and allows quick interaction without writing TypeScript code.

npx remote-voltmeter --help          # show global options and commands
npx remote-voltmeter info -h         # show per‑command help
npx remote-voltmeter info            # query instrument identification
npx remote-voltmeter measure vdc     # take DC voltage reading

The executable name corresponds to the bin field in package.json and will be installed globally if the package is installed with -g.

Basic Example

import VoltmeterDriver from '@elkamarado/remote-voltmeter';

const voltmeter = new VoltmeterDriver({
  host: '10.0.5.55',
  port: 3001,
  timeout: 5000,
});

// Connection
await voltmeter.connect();

// Get device information
const info = await voltmeter.getDeviceInfo();
console.log(info.model); // GDM-9061

// Measure DC voltage
const result = await voltmeter.measureVoltageDC();
console.log(`${result.value} V`);

// Disconnect
await voltmeter.disconnect();

🔧 API Methods

Connection and Initialization

// Connect to device
await voltmeter.connect();

// Disconnect from device
await voltmeter.disconnect();

// Get device information
const info = await voltmeter.getDeviceInfo();

// Reset device
await voltmeter.reset();

// Check connection
const connected = voltmeter.isConnected();

Voltage Measurements

// DC Voltage (constant)
const vdc = await voltmeter.measureVoltageDC('10V');
// Result: { value: 5.123, unit: 'V', function: 'VDC', timestamp: ... }

// AC Voltage (alternating)
const vac = await voltmeter.measureVoltageAC('100V');

// Automatic range (default)
const auto = await voltmeter.measureVoltageDC('AUTO');

Current Measurements

// DC Current (constant)
const idc = await voltmeter.measureCurrentDC('1A');

// AC Current (alternating)
const iac = await voltmeter.measureCurrentAC('10A');

Resistance Measurements

// Resistance
const resistance = await voltmeter.measureResistance('1kΩ');
// Result: { value: 1234.56, unit: 'Ω', ... }

// Continuity test (buzzer mode)
const continuity = await voltmeter.continuity();

// Diode test
const diode = await voltmeter.diodeTest();

// Frequency measurement
const frequency = await voltmeter.measureFrequency();

Range Control

// Set range manually
await voltmeter.setRange('100V');

// Enable automatic range selection
await voltmeter.enableAutoRange();

// Disable automatic range selection
await voltmeter.disableAutoRange();

Trigger Operations

// Configure trigger
await voltmeter.setTrigger({
  source: 'MANUAL',      // 'BUS', 'INTERNAL', 'EXTERNAL', 'MANUAL'
  delay: 0,              // delay in seconds
  count: 1,              // number of measurements
});

// Initiate trigger
await voltmeter.triggerInitiate();

// Get value from trigger memory
const value = await voltmeter.triggerFetch();

Display Control

// Display text on screen (max 6 characters)
await voltmeter.displayText('HELLO');

// Clear display
await voltmeter.clearDisplay();

// Display control (on/off, brightness)
await voltmeter.setDisplay({
  enabled: true,
  text: 'TEST',
  brightness: 100,
});

Diagnostics and Status

// Get operation status
const opStatus = await voltmeter.getOperationStatus();

// Get questionable status
const questionStatus = await voltmeter.getQuestionableStatus();

// Get and clear error
const error = await voltmeter.getError();
await voltmeter.clearErrors();

📊 Data Types

MeasurementFunction

type MeasurementFunction =
  | 'VDC'        // DC Voltage
  | 'VAC'        // AC Voltage
  | 'IDC'        // DC Current
  | 'IAC'        // AC Current
  | 'RESISTANCE' // Resistance
  | 'CONTINUITY' // Continuity
  | 'DIODE'      // Diode test
  | 'FREQUENCY'  // Frequency
  | 'PERIOD'     // Period
  | 'TEMPERATURE'// Temperature
  | 'CAPACITANCE'// Capacitance

MeasurementResult

interface MeasurementResult {
  value: number;              // Numeric value
  unit: string;               // Unit of measurement
  function: MeasurementFunction;
  timestamp: number;          // Measurement time (ms)
}

ConnectionOptions

interface ConnectionOptions {
  host: string;               // Device IP address
  port: number;               // SCPI port (usually 3001)
  timeout?: number;           // Command timeout (ms)
  reconnect?: boolean;        // Automatic reconnection
  reconnectInterval?: number; // Reconnection interval (ms)
}

🎞️ Events

voltmeter.on('connected', () => {
  console.log('Device connected');
});

voltmeter.on('disconnected', () => {
  console.log('Device disconnected');
});

voltmeter.on('error', (err) => {
  console.error('Error:', err);
});

voltmeter.on('timeout', (err) => {
  console.error('Timeout:', err);
});

voltmeter.on('unsolicited', (data) => {
  console.log('Unsolicited data:', data);
});

💡 Examples

Example 1: Simple Measurement

const voltmeter = new VoltmeterDriver({
  host: '10.0.5.55',
  port: 3001,
});

try {
  await voltmeter.connect();
  
  const result = await voltmeter.measureVoltageDC();
  console.log(`Voltage: ${result.value} V`);
  
  await voltmeter.disconnect();
} catch (error) {
  console.error('Error:', error);
}

Example 2: Multiple Measurements

const measurements = [];

for (let i = 0; i < 10; i++) {
  const result = await voltmeter.measureVoltageDC();
  measurements.push(result.value);
  
  // Pause between measurements
  await new Promise(resolve => setTimeout(resolve, 1000));
}

const average = measurements.reduce((a, b) => a + b) / measurements.length;
console.log(`Average value: ${average} V`);

Example 3: Event Handling

voltmeter.on('connected', () => {
  console.log('✓ Connected');
});

voltmeter.on('error', (err) => {
  console.error('✗ Error:', err.message);
  // Automatic reconnection may occur
});

await voltmeter.connect();

🔌 SCPI Commands

The library supports the following SCPI commands:

• Identification: *IDN?, *RST, *CLS
• Configuration: CONFigure:VOLTage:DC/AC, CONFigure:CURRent:DC/AC, CONFigure:RESistance, etc.
• Measurements: MEASure?, MEASure:VOLTage:DC?, MEASure:CURRent:DC?, etc.
• Range: RANGE, RANGE:AUTO ON/OFF
• Trigger: TRIGger:SOURce, TRIGger:DELay, TRIGger:COUNt, INIT, FETCh?
• Display: DISPlay, DISPlay:TEXT, DISPlay:CLEar, DISPlay:BRIGhtness
• Status: STATus:OPERation?, STATus:QUEStionable?, STATus
• System: SYSTem:ERRor?, SYSTem:TIME

The complete list of commands is defined in the ScpiCommand enum in src/types.ts.

⚙️ Technical Details

SCPI Protocol

• Interface: TCP/IP (RS232 through network gateway)
• Port: 3001 (typical for GDM-9061)
• Encoding: UTF-8
• Command separator: \n (added automatically)

Command Processing

• All commands are asynchronous and return Promise
• Commands are queued when sent
• Device responses are matched with sent commands
• Default timeout is 5000ms for each command

🐛 Error Handling

try {
  await voltmeter.connect();
  const result = await voltmeter.measureVoltageDC();
} catch (error) {
  if (error.message === 'Not connected') {
    console.log('No connection to device');
  } else if (error.message.includes('timeout')) {
    console.log('Command took too long to execute');
  } else {
    console.log('Unknown error:', error);
  }
}

📝 License

MIT

👨‍💻 Author

Created for the Remote Voltmeter Control System project

🔗 Links

• GW Instek GDM-9061 Manual
• SCPI standard: IEEE 488.2