The rules governing the arrangement of words, characters, and data within a program block are called the block format. Historically, CNC systems used fixed-order formats and delimiter (HT or TAB) block formats. These two formats are outdated, and the variable-address block format, also known as the word-address format, is widely used both domestically and internationally. In this format, the program word length is not fixed, and the number of program words is also variable. Most CNC systems allow the program words to be arranged arbitrarily, hence it is a variable block format. However, in most cases, for ease of writing, input, checking, and verification, program words are conventionally arranged in a certain order within the program block.
N03 is the program segment number; G02 indicates that the machining trajectory is a clockwise arc; X+053 and Y+053 represent the coordinates of the endpoint of the machined arc; I0 and J+053 represent the coordinates of the center of the machined arc; F031 is the machining feed rate; S04 is the spindle speed; T04 is the tool number used; M03 is the auxiliary function instruction; LF is the program segment end instruction; / is the skip selection instruction. The function of the skip selection instruction is to allow the operator to choose whether to execute the program segment with the skip selection instruction, provided that the program remains unchanged. The selection method is usually achieved by turning the skip selection switch on the operation panel to ON or OFF to execute the program segment with "/".
