# Range of freely user-definable M/H numbers

The maximum number range from 0 to 65.535 is provided for M / H numbers.

## Release Note

The actually available range is limited depending on the version and can be found in the documentation [SYSP].

This is where you will also find details of the limits regarding the maximum number of M and H functions in each CNC block as well as the maximum number of simultaneously active 'late' synchronisations per channel and per axis.

The M functions reserved in compliance with DIN 66025 pose a further restriction (see the next Section: "Default M functions").