> ## Documentation Index
> Fetch the complete documentation index at: https://devzone.nayax.com/llms.txt
> Use this file to discover all available pages before exploring further.

# doPinpadTransaction

The `doPinpadTransaction` method is used in the PinPad flow to continue an ongoing EMV transaction after the initial card capture. This is primarily done to prompt the cardholder to enter a PIN or to exchange additional EMV data (tags) with the payment terminal, advancing the EMV state machine.

<Warning>
  **Contact Transactions Only**

  This method is relevant to contact transactions (inserted cards), which require a controlled multi-step EMV dialogue involving the terminal and the PIN pad.
</Warning>

## Request

<Note>
  **JSON-RPC 2.0**

  All methods in TweezerComm follow a JSON-RPC 2.0 structure. See [Get Started](/docs/integrate-pos-device/tweezercomm/tweezercomm-get-started) for more details on how the requests are structured and sent.
</Note>

In the request, ensure to configure the following:

* The `method` field must be set to `doPinpadTransaction`.
* The `service` must be set to `engine` in the params.

The request includes the service name and a dictionary of EMV tags that the host system must return to the terminal/card to proceed with the transaction dialogue.

```json theme={null}
{
   "jsonrpc": "2.0",
   "method": "doPinpadTransaction",
   "id": "123454352",
   "params": [
       "engine",
       {
           "tags": {
               "95": "tag value",
               "9F02": "tag value"
           }
       }
   ]
}
```

### Request Parameters

The table below describes the request parameters for this method.

| Name   | Type            | Description                                                                                                                                  |
| :----- | :-------------- | :------------------------------------------------------------------------------------------------------------------------------------------- |
| `tags` | JSON of strings | A dictionary containing the required EMV Tag-Value pairs that the host system must return to the card/terminal to continue the EMV dialogue. |

## Response

A successful response indicates that the PinPad transaction state has advanced, either by successfully collecting the PIN from the cardholder or by completing an EMV data exchange round.

```json theme={null}
{
   "jsonrpc": "2.0",
   "id": "123454352",
   "result": {
       "statusCode": 0,
       "statusMessage": "ok",
       "pem": EMVMANAGER_CONTACT,
       "tags": {
           "95": "tag value",
           "9F02": "tag value",
           "5A": "tag value",
           "5F34": "tag value",
           "5F2A": "tag value",
           "9F02": "tag value",
           "9F03": "tag value",
           "9A": "tag value",
           "9C": "tag value",
           "9F1A": "tag value",
           "9F21": "tag value",
           "9F37": "tag value",
           "9F36": "tag value",
           "9F26": "tag value",
           "9F27": "tag value"
       }
   }
}
```

### Response Parameters

Below is a table with all the possible response parameters and their description:

| Name            | Type            | Description                                                                                                                                                 |
| :-------------- | :-------------- | :---------------------------------------------------------------------------------------------------------------------------------------------------------- |
| `statusCode`    | integer         | The PinPad transaction status. A value of `0` indicates success.                                                                                            |
| `statusMessage` | string          | The transaction message (e.g., `ok`).                                                                                                                       |
| `pem`           | integer         | POS Entry Mode, indicating the method of card entry (e.g., `EMVMANAGER_CONTACT`).                                                                           |
| `tags`          | JSON of strings | A dictionary containing updated or new EMV Tag-Value pairs from the card/terminal, including information like the masked PAN (`5A`) or updated cryptograms. |

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