Dealing with Machine Capability

Not all machines can handle canned drill cycles the same way. Some machines can only handle drill cycles in the XY plane (constant Z value). Other can handle drill cycles in all major planes (XY, YZ and ZX), while others can handle them in any plane.

A new DF2 file parameter, Output Cycles by Planes, allows the GPP2 user to specify how drill cycles are handled in GPP2. It is a multi-choice parameter, with the following options:

• Never: canned drill cycles are not supported, in any plane.

• XY Plane: drill cycles are supported in the XY plane only.

• Major Planes: drill cycles are supported in all major planes.

• Any Plane: drill cycles are supported in any plane.

The selected option is copied to a GPP2 system flag, CYC_CTRL_BYPLANE, which can be changed by the GPP2 program in order to override the original setting. After the system flag is initialized from the DF2 parameter, GPP2 will follow the setting of the CYC_CTRL_BYPLANE variable.

In order to set or check the value of CYC_CTRL_BYPLANE, it is advised to use the predefined GPP2 constants, DF2_NONE, DF2_XYONLY, DF2_MAJORPLANES and DF2_ANYPLANE. They correspond to the four options listed above.

Unlike subroutines or arcs, where GPP2 can convert them to something else in case they are not supported on a given plane, there is no such built-in mechanism for cycles. The way to simulate a canned drill cycle may vary from machine to machine, and cannot be easily automated inside GPP2. The burden of handling non-supported cycles is left to the EX2 programmer.

GPP2 will set on a special new system variable, CYC_MANUAL, which indicates that a given cycle block is not supported by the machine, based on the cycle plane and the DF2 file parameter. In cases where the cycle is supported, the system variable will be set to off. The EX2 program should execute different commands based on the set status of CYC_MANUAL.