State canned cycle & subroutines.

1 Answer

Answer :

Canned cycle (Fixed cycle):

It is defined as a set of instructions, inbuilt or stored in the system memory, to perform a fixed sequence of operations.

[1] It reduces programming time and effort.

[2] Canned cycle is used for repetitive and commonly used machining operations.

[3] To save the repetition of programming of common operations, the cycle is used called affixed cycle/canned cycle.

[4] The sequence of standard cycle of operation is stored in the memory of the computer.

[5] When that information is required at the time of machining is activated from memory, by using proper G–code.

[6] One of the most frequently used canned cycles is the drilling cycles.


Subroutine called, subprogrammes, are a powerful time saving technique. It provides the capability of programming certain fixed sequence or frequently repeated operations.

These are independent programs with all the operations of a usual part program.

[1] Subroutines are stored in the memory under separate program numbers.

[2] When particular operation is required in the program, the associated subroutine is called for completing the operation.

[3] Subroutine also called as sub programs.

[4] After completion of subroutine the control returns to main program. 

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