---
title: beatAndTempoProc
framework: audiotoolbox
role: symbol
role_heading: Instance Property
path: audiotoolbox/hostcallbackinfo/beatandtempoproc
---

# beatAndTempoProc

Your callback function that provides beat and tempo information to an audio unit. May be NULL.

## Declaration

```swift
var beatAndTempoProc: HostCallback_GetBeatAndTempo?
```