# SendDigits
<a name="send-digits"></a>

Send up to 50 dual tone multi-frequency (DTMF) digits on any leg of a call. The signals can include the following:
+ Numbers 0 thru 9
+ Special characters star (\*) and pound (\#)
+ Network control signals A, B, C, D
+ The comma character (,). This signal adds a 0.5 second delay between the previous and next signals.

**Topics**
+ [Using the SendDigits action](#send-digits-action)
+ [Handling ACTION\_SUCCESSFUL events](#send-digit-success)
+ [Handling ACTION\_FAILED events](#send-digit-fail)
+ [Call flow](#send-digits-call-flow)

## Using the SendDigits action
<a name="send-digits-action"></a>

The following example shows a typical `SendDigits` action:

```
{
    "SchemaVersion": "1.0",
    "Actions":[
        {
            "Type": "SendDigits",
            "Parameters": {
                "CallId": "{{call-id-1}}", // required
                "Digits": "{{,,*1234,56,7890ABCD#}}", // required
                "ToneDurationInMilliseconds": {{100}} // optional
            }
        }
    ]
}
```

**CallId**  
*Description* – The `CallId` of a participant in the `CallDetails` of the AWS Lambda function invocation  
*Allowed values* – A valid call ID  
*Required* – Yes  
*Default value* – None

**Digits**  
*Description* – The digits to be sent on the call leg that corresponds to the `CallId`  
*Allowed values* – 0-9, \*, \#, A, B, C, D, comma (,)  
*Required* – Yes  
*Default value* – None

**ToneDurationInMilliseconds**  
*Description* – The amount of time allowed, in milliseconds, to transmit each digit.  
*Allowed values* – Any integer between 50 and 24000  
*Required* – No  
*Default value* – 250

## Handling ACTION\_SUCCESSFUL events
<a name="send-digit-success"></a>

The following example shows a typical `ACTION_SUCCESSFUL` event for the `SendDigits` action.

```
{
    "SchemaVersion": "1.0",
    "Sequence": {{3}},
    "InvocationEventType": "ACTION_SUCCESSFUL",
    "ActionData": {
        "Type": "SendDigits",
        "Parameters": {
            "Digits": "{{1,2A#}}",
            "ToneDurationInMilliseconds": {{100}},
            "CallId": "{{call-id-1}}"
        },  
    "CallDetails": { 
        ...
        }
    }
}
```

## Handling ACTION\_FAILED events
<a name="send-digit-fail"></a>

The following example shows a typical `ACTION_FAILED` event for the `SendDigits` action.

```
{
    "SchemaVersion": "1.0",
    "Sequence": {{3}},
    "InvocationEventType": "ACTION_FAILED",
    "ActionData": {
        "Type": "SendDigits",
        "Parameters": {
            "Digits": "{{1,2A#}}",
            "ToneDurationInMilliseconds": {{20000000}},
            "CallId": "{{call-id-1}}"
        },
    "ErrorType": "InvalidActionParameter",
    "ErrorMessage": "ToneDuration parameter value is invalid."
    },
    "CallDetails": {
        ...
        }
    }
}
```

## Call flow
<a name="send-digits-call-flow"></a>

The following diagram shows the program flow for sending digits from a caller to a callee.

![Diagram showing the program flow of the SendDigits action.](http://docs.aws.amazon.com/chime-sdk/latest/dg/images/send-digits-1.png)