G-code is a collection of codes or functions that are part of numerical control or NC programming language. The Electronic Industries Alliance developed the earliest versions of this type of NC coding during the 1960’s. Serving as the standard CNC in the United States, the coding has undergone some enhancements. At present, a version adopted in February 1980 and known as RS274D is the standard in the United States and various other countries around the world. However, a different standard, known as DIN 66025, is commonly used in Europe.
All types of code within the structure of NC coding focus on different functions. With G-code, the focus is on the actual positioning of the tool in order to accomplish the appropriate task. This contrasts with other types of code within the system. For example, S-code has to do with the speed of the tool, while F-code addresses the feed of the tool.
While G-code may form the basis for the configuration of many different types of tools, it is not unusual for manufacturers to create and add their own unique functions that are outside the scope of NC coding altogether. While it is true that the coding may be present in some form, the addition of extensions and enhancements sometimes will limit the ability of the tool to interface with other tools.
Because G-code is a preparatory code, it does find inclusion in many different manufactured items. The use of the code is helpful in triggering specific action on the part of the tool in question. Some of the actions that G-code may trigger include moving forward or backward in a straight line or at an angle. The code can tell the machine to move quickly or at a slower pace. G-code can be used to create a set of sequenced events that occur as a bloc, such as drilling a hole in a piece of metal or wood, moving the object, and drilling a second hole before releasing the object and preparing for the receipt of a new one.