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# peripheralManagerIsReady(toUpdateSubscribers:)

Tells the delegate that a local peripheral device is ready to send characteristic value updates.

```
optional func peripheralManagerIsReady(toUpdateSubscribers peripheral: CBPeripheralManager)
```

## Parameters

`peripheral`

The peripheral manager that sends characteristic value updates.

## Discussion

When a call to the [`updateValue(_:for:onSubscribedCentrals:)`](/documentation/CoreBluetooth/CBPeripheralManager/updateValue(_:for:onSubscribedCentrals:)) method fails because the underlying queue used to transmit the updated characteristic value is full, Core Bluetooth calls the [`peripheralManagerIsReady(toUpdateSubscribers:)`](/documentation/CoreBluetooth/CBPeripheralManagerDelegate/peripheralManagerIsReady(toUpdateSubscribers:)) method when more space in the transmit queue becomes available. You can then implement this delegate method to resend the value.

---

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