Automatic operation is to operate the machine according to the created
program. It includes memory and MDI operations. (See Section III–4).
Fig.1.2 (a) Tool movement by programming
After the program is once registered in memory of CNC, the machine can
be run according to the program instructions. This operation is called
Fig.1.2 (b) Memory operation
After the program is entered, as an command group, from the MDI
keyboard, the machine can be run according to the program. This
operation is called MDI operation.
CNC MDI keyboard
Fig.1.2 (c) MDI operation
In this mode of operation, the program is not registered in the CNC
memory. It is read from the external input/output devices instead. This
is called DNC operation. This mode is useful when the program is too
large to fit the CNC memory.
D Memory operation
D MDI operation
D DNC operation