> ## 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.

# Reader Messages

Reader messages are critical for communicating the status of the card reader to users during a transaction. The EMV Core SDK provides a `ReaderMessageEvent` callback to relay these messages, which can be displayed in the application’s user interface.

The sections below contain tables describing the different reader messages that can be displayed.

## Main reader messages

These are the messages sent for the reader's main operational states, transitions, and error conditions:

| Category               | Hex (Internal) | Decimal (API) | Message Details                                                  |
| :--------------------- | :------------- | :------------ | :--------------------------------------------------------------- |
| **Main States**        | 0x00           | 0             | (Blank Screen)                                                   |
|                        | 0x01           | 1             | Present card                                                     |
|                        | 0x11           | 17            | Welcome                                                          |
|                        | 0x23           | 35            | Card read OK Remove card                                         |
|                        | 0x04           | 4             | Please remove card                                               |
|                        | 0x0D           | 13            | Approved sign                                                    |
| **Recovery States**    | 0x05           | 5             | Please present one card only                                     |
|                        | 0x03           | 3             | Please present one card only                                     |
|                        | 0x27           | 39            | Read error Please try again                                      |
| **Stateless Messages** | 0x12           | 18            | Thank You                                                        |
|                        | 0x15           | 21            | Please Use Another Card                                          |
|                        | 0x19           | 25            | Please Wait                                                      |
|                        | 0x1A           | 26            | International Card, Please Swipe!                                |
| **Online Results**     | 0x24           | 36            | Authorizing Please wait                                          |
|                        | 0x06           | 6             | Approved                                                         |
|                        | 0x09           | 9             | Not Approved                                                     |
| **Offline Results**    | 0x07           | 7             | Approved                                                         |
|                        | 0x08           | 8             | Not Approved                                                     |
| **Error States**       | 0x1E           | 30            | Timed Out Please insert or swipe card                            |
|                        | 0x25           | 37            | Communication Failure                                            |
|                        | 0x26           | 38            | Please insert or swipe card                                      |
|                        | 0x0A           | 10            | Terminated                                                       |
|                        | 0x0B           | 11            | PIN Entry Required – see attendant                               |
|                        | 0x0C           | 12            | See Phone                                                        |
|                        | 255            | N/A           | Deprecated since SDK v1.5. Replaced by indexes 201 to 220 below. |

## Other messages from EMV Core

Since SDK v1.5, EMV Core sends additional status messages using dedicated indexes instead of the single index 255 used in earlier versions. You can overwrite each message's default text with the corresponding configuration key.

| Decimal (API) | Default text                                             | Configuration key             |
| :------------ | :------------------------------------------------------- | :---------------------------- |
| 201           | Loading...                                               | `SAT_MSG_LOADING`             |
| 202           | Welcome                                                  | `SAT_MSG_READER_IDLE`         |
| 203           | Vending item                                             | `SAT_MSG_VEND_ONLINE`         |
| 204           | Thank You! Total: X.XX                                   | `SAT_MSG_RESULT`              |
| 205           | Declined                                                 | `SAT_MSG_DECLINED`            |
| 206           | Please select an item                                    | `SAT_MSG_SELECT`              |
| 207           | Error Please Try Again                                   | `SAT_MSG_ERROR`               |
| 208           | Please / Wait ...                                        | `SAT_MSG_DISABLED`            |
| 209           | No selection Cancelling                                  | `SAT_MSG_CANCEL`              |
| 210           | Starting over                                            | `SAT_MSG_SELECTION_TIMEOUT`   |
| 211           | Not enough credit                                        | `SAT_MSG_LOW_BALANCE`         |
| 212           | Updating...                                              | `SAT_MSG_BUSY`                |
| 213           | Insert, swipe or Try another card                        | `SAT_MSG_SWIPE_ALL`           |
| 214           | Amount too small                                         | `SAT_MSG_MIN_PRICE`           |
| 215           | Credit received Select product                           | `SAT_MSG_SELECT_NOCARD`       |
| 216           | Card not recognized                                      | `SAT_MSG_CARD_NOT_RECOGNIZED` |
| 217           | Authorizing...                                           | `SAT_MSG_CLP_AUTHORIZING`     |
| 218           | Approved Balance:                                        | `SAT_MSG_CLP_APPROVED`        |
| 219           | Varies. Firmware version or IP address at startup.       | `SAT_MSG_SYSTEM_INFO`         |
| 220           | Varies. Set by the host using the `ShowMessage` command. | `SAT_MSG_CUSTOM_MESSAGE`      |

<Note>
  Indexes 221 to 250 are reserved for future EMV Core messages.
</Note>