Another way to use a CNC machine without a computer is by using a DNC system (Direct Numerical Control). This system allows you to send a program directly to the CNC controller via a serial or Ethernet connection, thus eliminating the need for a computer. However, this method also requires a specific software and hardware setup.
Another way is using a conversational programming, which is a type of programming that allows the operator to input commands using natural language instead of G-code. This can be done through a keyboard or a touch screen interface. This method is more user-friendly, but it is also less common, and it is not as versatile as G-code programming.
In summary, while it is possible to operate a CNC machine without a computer, it is not the most efficient or precise way of doing so. The use of computer programs and specialized controllers is the most common way to control CNC machines for precision and efficiency.