Oakrey.AT 3.1.2

Oakrey.AT

Overview

Oakrey.AT is a .NET 10 library for communicating with AT command-based devices such as modems, cellular modules, and IoT peripherals. It provides a strongly-typed, async handler model built around ITransmitter, covering audio control, call management, SMS, phonebook operations, and eCall (IVS/PSAP) support.

Main Features

Audio Control

• Open and close I2C logical channels.
• Configure master clock control.
• Write data to I2C peripherals.

Call Management

• Answer incoming calls.
• Dial numbers, names, or phonebook entries.
• Enable or disable calling line identification.
• Manage automatic answering and call status reporting.
• Retrieve incoming call information and hang up calls.

eCall Support

• Enable or disable eCall features.
• Configure and test eCall settings (IVS and PSAP).
• Manage in-band modem activation and loudspeaker/microphone URC controls.
• Factory class HandlerFactoryIVS for convenient IVS handler creation.

General Device Management

• Retrieve device serial numbers, signal power, and operator information.
• Check communication status with the device.

Phonebook Operations

• Add, delete, and search contacts.
• Retrieve phonebook entries by index or range.
• Configure SIM phonebook storage.

SMS Handling

• Send and receive SMS messages in text or PDU mode.
• Manage SMS storage and delete messages.
• Retrieve a list of all stored SMS messages.

Extensibility

• Layered base classes for custom AT command handlers.
• ATCommandException for structured error propagation.
• Per-command reply timeout (500 ms default).

Architecture

The library is structured around a handler hierarchy. Each handler represents one AT command and exposes an async Execute method. Device access is serialized via a SemaphoreSlim passed into every call.

classDiagram
    direction TB
    class IHandler {
        <<interface>>
        +Command: string
        +Parameter: string
        +ATCommandType: ATCommandType
        +ProcessReplay(data, ct)
    }
    class HandlerBase~TSelf~ {
        <<abstract>>
    }
    class ReplayHandler~TSelf, TReplay~ {
        <<abstract>>
        #Run(transmitter, deviceLock, data, ct) Task~TReplay~
    }
    class StatusHandler~TSelf~ {
        #HandleStatusReply(data, ct)
    }
    class DialNumberHandler
    class SendSMSMessageToNumberHandler

    IHandler <|-- HandlerBase~TSelf~
    HandlerBase~TSelf~ <|-- ReplayHandler~TSelf,TReplay~
    ReplayHandler~TSelf,TReplay~ <|-- StatusHandler~TSelf~
    StatusHandler~TSelf~ <|-- DialNumberHandler
    StatusHandler~TSelf~ <|-- SendSMSMessageToNumberHandler

The ITransmitter interface decouples the library from any specific serial or socket transport:

public interface ITransmitter
{
    void Send(string command);
}

Incoming device responses are routed back to the awaiting handler by calling ProcessReplay on the matching IHandler.

Requirements

• .NET 10 or higher
• Oakrey.Async 2.1.0
• Oakrey.Log 2.0.0

Installation

.NET CLI

dotnet add package Oakrey.AT

Package Manager Console

Install-Package Oakrey.AT

NuGet Package Manager

1. Open your project in Visual Studio.
2. Navigate to Tools > NuGet Package Manager > Manage NuGet Packages for Solution.
3. Search for Oakrey.AT and click Install.

Usage

1. Implement ITransmitter

Provide a transport-specific implementation that writes the formatted AT command string to the device:

public class SerialTransmitter : ITransmitter
{
    private readonly SerialPort _port;

    public SerialTransmitter(SerialPort port) => _port = port;

    public void Send(string command) => _port.WriteLine(command);
}

2. Route device responses

When data arrives from the device, call ProcessReplay on the handler that is currently waiting:

activeHandler.ProcessReplay(receivedLine, cancellationToken);

3. Execute a command

Each handler is instantiated independently. Pass the transmitter and a shared SemaphoreSlim to serialize access across concurrent callers:

SemaphoreSlim deviceLock = new SemaphoreSlim(1, 1);
ITransmitter transmitter = new SerialTransmitter(port);

// Dial a number
DialNumberHandler dialHandler = new DialNumberHandler();
bool success = await dialHandler.Execute(transmitter, deviceLock, "+420123456789", CancellationToken.None);

// Send an SMS
SendSMSMessageToNumberHandler smsHandler = new SendSMSMessageToNumberHandler();
bool sent = await smsHandler.Execute(transmitter, deviceLock, "+420123456789", "Hello", CancellationToken.None);

4. eCall IVS setup

Use HandlerFactoryIVS to create the standard set of IVS handlers:

ECallFeatureEnableHandler enableHandler = HandlerFactoryIVS.CreateECallFeatureEnableHandler();
await enableHandler.Execute(transmitter, deviceLock, CancellationToken.None);

Extensibility

To add a custom AT command, inherit from StatusHandler<TSelf> (for OK/ERROR responses) or ReplayHandler<TSelf, TReplay> (for typed responses):

public class MyCustomHandler : StatusHandler<MyCustomHandler>
{
    public override string Command => "AT+MYCMD";
    public override ATCommandType ATCommandType => ATCommandType.EXECUTION;
    public override string Parameter => "";

    public Task<bool> Execute(ITransmitter transmitter, SemaphoreSlim deviceLock, CancellationToken cancellationToken)
        => Run(transmitter, deviceLock, GetCommandFormat(Command, ATCommandType, Parameter), cancellationToken);
}

Project Information

License

This project is licensed under the MIT License. See the LICENSE file for details.