Identification of axes and channels

Channel identification

Channels are identified by their index on the PLC interface. The sequence of channels corresponds to the configuration sequence.

The channel first configured is addressed by the index 0 and the last channel configured out of n channels is addressed by the index n – 1.

If an invalid channel index is transferred to a function, the return value ERR_INVALID_CHAN (defined in kernelv.h) is returned.

If functions supply channel numbers as the return value, the associated channel index can be determined by means of the relationship

channel index = channel number - 1

.

Axis identification

Axes are identified by their index on the PLC interface. The sequence of axes corresponds to the configuration sequence.

The axis first configured is addressed by the index 0 and the last axis configured out of n axes is addressed by the index n – 1.

If an invalid axis index is transferred to a function, the return value ERR_INVALID_AX (defined in kernelv.h) is returned.