> For the complete documentation index, see [llms.txt](https://docs.coda.co/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.coda.co/codapay/hosted-payment-page-integration/initiate-usd-transactions/request-flow.md).

# Request Flow

## <mark style="color:purple;">Call Flow of USD Transaction Initiation</mark>

<figure><img src="/files/PuzN9uwPLD5q7FoP1GLQ" alt=""><figcaption></figcaption></figure>

There are no changes to the Codapay API structure. Simply send the desired ISO 4217 currency code in the "currency" parameter of the Init request.

For USD, the ISO code is `840`.

## <mark style="color:purple;">**Request Flow**</mark>

1. When the partner needs to request US dollars, the request parameter currency must use 840.
2. When the user pays, Coda payment page will convert and display in local currency.
3. Coda payment page shows the price in local currency, based on the conversion rate of the day in the Coda system.

## <mark style="color:purple;">Sample Request and Response</mark>

{% tabs %}
{% tab title="v2.0 Request" %}

```json
{
    "initRequest": {
        "country": 158,
        "payType": 0,
        "apiKey": "live_****************************",
        "projectId": 21 //This field is only needed for v2.0 API
        "orderId": "12321312321314",
        "currency": 840, //Currency code (e.g., 840 = USD)
        "items": [
            {
                "code": "1",
                "price": 1000.00,
                "name": "Test Item"
            }
        ],
        "profile": {
            "entry": [
                {
                    "key": "user_id",
                    "value": "105"
                }
            ]
        }
    }
}
```

{% endtab %}

{% tab title="v1.0 Request " %}

```json
{
    "initRequest": {
        "country": 158,
        "payType": 82,
        "apiKey": "e944d4*****************",
        "orderId": "12321312321314",
        "currency": 840, //Currency code (e.g., 840 = USD)
        "items": [
            {
                "code": "1",
                "price": 1000.00,
                "name": "Test Item"
            }
        ],
        "profile": {
            "entry": [
                {
                    "key": "user_id",
                    "value": "105"
                }
            ]
        }
    }
}

```

{% endtab %}

{% tab title="Successful Response" %}

```json
{
    "initResult": {
        "redirectUrl": "https://airtime.codapayments.com/airtime/begin?txn_id=7714940366302672840",
        "resultCode": 0,
        "txnId": 7714940366302672840
    }
}
```

{% endtab %}

{% tab title="Failed Response" %}

```json
{
    "initResult": {
        "resultCode": 103,
        "resultDesc": "This transaction has been cancelled. No charges were made. (error:103)",
        "txnId": 0
    }
}
```

{% endtab %}
{% endtabs %}

An example is provided below, using Coda's channel selection page paytype=0. After requesting to pull up the page, users can see the channels they can choose from along with their respective local prices.


---

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