任何系统是由连通组件组成，对于cnc设备，这些组件可能是主控制器，伺服放大器或步进驱动器，马达，编码器，极限开关，按钮，主轴变频器，刀库管理PLC等。设备制造商必须选择、加载和连接这些部分在一起来组成一个完整的系统。(HAL stands for Hardware Abstraction Layer. At the highest level, it is simply a way to allow a number of building blocks to be
loaded and interconnected to assemble a complex system. The Hardware part is because HAL was originally designed to make
it easier to configure LinuxCNC for a wide variety of hardware devices. Many of the building blocks are drivers for hardware
devices. However, HAL can do more than just configure hardware drivers.)