markdown/gh_discussions/Query/3023.md

# Clock Division

Tool: OpenSTA

Subcategory: Constraint definition

## Conversation

### Ziad-cyber
How to define a constraint on a generated clock that's divided by 2 from a master clock source?

### vijayank88
OpenROAD flow accepts all standard SDC formats. Just browse it and implement the same.
OpenSTA doc found [here](https://github.com/The-OpenROAD-Project/OpenSTA/blob/master/doc/OpenSTA.pdf)

### maliberty
In particular see create_generated_clock