import { ByteArray } from '../types.js';
/**
 * Converts a byte array to a byte array containing hexadecimal character codes.
 * Each byte becomes two bytes representing its hex digits.
 *
 * @param bytes - The byte array to convert.
 * @returns A byte array with hexadecimal character codes.
 *
 * @example
 * ```typescript
 * bytesToHexBytes(new Uint8Array([255])) // Returns bytes for 'FF'
 * ```
 */
export declare function bytesToHexBytes(bytes: ByteArray): ByteArray;