/**
 * SerialSession — transport-agnostic serial session interface and Web Serial API implementation.
 *
 * The interface is identical regardless of the underlying transport (Web Serial API in browser,
 * Node.js serialport in standalone/test builds). The concrete implementations differ only in
 * how they talk to the hardware; the rest of the stack (CWKeyer, ProtocolAdapter) uses only
 * this interface and is never aware of the transport layer.
 */
export interface SerialSession {
    writeBytes(data: Uint8Array): Promise<void>;
    writeText(text: string): Promise<void>;
    disconnect(): Promise<void>;
    on(listener: (data: Uint8Array) => void): void;
    off(listener: (data: Uint8Array) => void): void;
}
export declare function isWebSerialSupported(): boolean;
export declare function requestSerialPort(options?: SerialPortRequestOptions): Promise<SerialPort>;
export declare function openSerialPort(port: SerialPort, options: SerialOptions): Promise<void>;
export declare function closeSerialPort(port: SerialPort): Promise<void>;
/**
 * Wraps an already-opened Web Serial API SerialPort into a SerialSession.
 * Uses the WHATWG Streams API (port.readable / port.writable).
 */
export declare function createWebSerialSession(port: SerialPort): SerialSession;
/**
 * Requests a Web Serial port, opens it, and returns a SerialSession.
 * Browser-only; throws if the Web Serial API is unavailable.
 */
export declare function connectSerialSession(serialOptions: SerialOptions, requestOptions?: SerialPortRequestOptions): Promise<SerialSession>;
/**
 * Silently reconnects using the first previously-granted Web Serial port.
 * Returns a connected SerialSession, or null if no port was previously granted
 * or if the Web Serial API is unavailable.
 * Does NOT show a port-picker dialog.
 */
export declare function autoConnectWebSerial(serialOptions: SerialOptions): Promise<SerialSession | null>;