以下是使用AVFoundation框架获取1秒音频样本缓冲区数据的示例代码：

import AVFoundation

class AudioSampleBufferDelegate: NSObject, AVCaptureAudioDataOutputSampleBufferDelegate {
    var audioData: [Float] = []

    func captureOutput(_ output: AVCaptureOutput, didOutput sampleBuffer: CMSampleBuffer, from connection: AVCaptureConnection) {
        guard let audioBuffer = CMSampleBufferGetAudioBufferListWithRetainedBlockBuffer(sampleBuffer, bufferListSizeNeededOut: nil, bufferListOut: nil, bufferListSize: MemoryLayout.size, blockBufferAllocator: nil, blockBufferMemoryAllocator: nil, flags: kCMSampleBufferFlag_AudioBufferList_Assure16ByteAlignment, blockBufferOut: nil) == noErr else {
            return
        }
        
        let audioBuffers = UnsafeBufferPointer(start: &audioBuffer.mBuffers, count: Int(audioBuffer.mNumberBuffers))
        
        for audioBuffer in audioBuffers {
            let frameCount = Int(audioBuffer.mDataByteSize) / MemoryLayout.size
            let samples = UnsafeBufferPointer(start: audioBuffer.mData?.assumingMemoryBound(to: Float.self), count: frameCount)
            audioData.append(contentsOf: samples)
        }
    }
}

// 创建AVCaptureSession
let captureSession = AVCaptureSession()

// 获取音频设备
guard let audioDevice = AVCaptureDevice.default(for: .audio) else {
    fatalError("Failed to get audio device")
}

// 创建音频输入
guard let audioInput = try? AVCaptureDeviceInput(device: audioDevice) else {
    fatalError("Failed to create audio input")
}

// 将音频输入添加到会话
if captureSession.canAddInput(audioInput) {
    captureSession.addInput(audioInput)
} else {
    fatalError("Failed to add audio input to capture session")
}

// 创建音频输出
let audioOutput = AVCaptureAudioDataOutput()
let audioSampleBufferDelegate = AudioSampleBufferDelegate()
audioOutput.setSampleBufferDelegate(audioSampleBufferDelegate, queue: DispatchQueue.main)

// 将音频输出添加到会话
if captureSession.canAddOutput(audioOutput) {
    captureSession.addOutput(audioOutput)
} else {
    fatalError("Failed to add audio output to capture session")
}

// 开始采集音频数据
captureSession.startRunning()

// 停止采集音频数据
captureSession.stopRunning()

// 获取音频数据
let audioSamples = audioSampleBufferDelegate.audioData

上述代码创建了一个AVCaptureSession来采集音频数据。通过AVCaptureAudioDataOutputSampleBufferDelegate代理方法captureOutput(_:didOutput:from:)来获取音频样本缓冲区数据，并将其存储在audioData数组中。最后，可以通过访问audioSampleBufferDelegate.audioData来获取完整的1秒音频样本缓冲区数据，其中包含了44100个浮点值。