import usb.core
import usb.util

# USB设备参数
VENDOR_ID = 0x0000  # 替换为实际的VID
PRODUCT_ID = 0x0001  # 替换为实际的PID
OUT_ENDPOINT = 0x01  # EP1 OUT端点
IN_ENDPOINT = 0x82   # EP2 IN端点 (注意: IN端点通常最高位设为1)
MAX_FIFO_SIZE = 64    # 最大FIFO长度

def find_usb_device():
    """查找并返回指定的USB设备"""
    dev = usb.core.find(idVendor=VENDOR_ID, idProduct=PRODUCT_ID)
    if dev is None:
        raise ValueError("设备未找到，请检查连接或VID/PID")
    return dev

def configure_device(dev):
    """配置USB设备"""
    # 如果是Linux，可能需要先detach内核驱动
    # if dev.is_kernel_driver_active(0):
    #    dev.detach_kernel_driver(0)
    
    # 设置配置
    dev.set_configuration()
    
    # 获取配置
    cfg = dev.get_active_configuration()
    intf = cfg[(0,0)]
    
    print("设备配置成功")
    return dev

def send_data(dev, data):
    """向OUT端点发送数据"""
    if len(data) > MAX_FIFO_SIZE:
        raise ValueError(f"数据长度超过最大FIFO大小({MAX_FIFO_SIZE}字节)")
    
    # 发送数据到EP1 OUT
    bytes_written = dev.write(OUT_ENDPOINT, data)
    print(f"发送成功: {bytes_written} 字节")
    return bytes_written

def receive_data(dev, max_length=MAX_FIFO_SIZE):
    """从IN端点接收数据"""
    # 从EP2 IN读取数据
    data = dev.read(IN_ENDPOINT, max_length)
    print(f"接收成功: {len(data)} 字节")
    return data

def main():
    try:
        # 查找并配置设备
        dev = find_usb_device()
        dev = configure_device(dev)
        
        # 示例数据发送
        test_data = b"Hello USB Device!"  # 测试数据
        send_data(dev, test_data)
        
        # 示例数据接收
        received_data = receive_data(dev)
        print("接收到的数据:", received_data)
        
    except usb.core.USBError as e:
        print(f"USB错误: {e}")
    except Exception as e:
        print(f"错误: {e}")
    finally:
        # 释放设备
        usb.util.dispose_resources(dev)

if __name__ == "__main__":
    main()