> For the complete documentation index, see [llms.txt](https://developer.magtek.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://developer.magtek.com/hardware/card-readers/mms-dyna-devices/dynaprox/documents/programmers-manuals/programmers-manual-commands/commands/transactions/cancel-transaction.md).

# Cancel Transaction

## Command 0x1008 - Cancel Transaction

The host can use this command to cancel a transaction in progress that it initiated using Command 0x1001 - Start Transaction.

Sequence of events:

{% stepper %}
{% step %}

### Host has already started a transaction

The host has already called Command 0x1001 - Start Transaction and the transaction is still in process.
{% endstep %}

{% step %}

### Construct the command request

The host constructs the command request in the format below.
{% endstep %}

{% step %}

### Send the command request

The host sends the command request to the device.
{% endstep %}

{% step %}

### Device sends a response

The device sends a response in the format below to the host:

* If the transaction is in a state where it cannot be canceled, the device’s response returns operation status detail: Failed, Device State Issue, Cannot Cancel.
* If there is no transaction in progress, the device’s response returns operation status detail: Failed, Device State Issue, No Transaction.
* If the device successfully cancels the transaction, the device’s response returns operation status detail: All Good, Requested Operation Was Successful, shows "CANCELED" and returns to the idle state. The display (if any) shows "CANCELED".
  {% endstep %}
  {% endstepper %}

## Table - Request Data for Command 0x1008 - Cancel Transaction

<table><thead><tr><th width="288.54541015625">Tag</th><th width="73.33331298828125">Len</th><th width="124.66668701171875">Value / Description</th><th width="74.33331298828125">Typ</th><th width="76.66668701171875">Req</th><th width="94.666748046875">Default</th></tr></thead><tbody><tr><td>Beginning of any wrappers, at minimum including Request Message</td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>1008 = Command 0x1008 - Cancel Transaction</td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>No parameters.</td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>End of any wrappers, at minimum including Request Message</td><td></td><td></td><td></td><td></td><td></td></tr></tbody></table>

## Table - Response Data for Command 0x1008 - Cancel Transaction

<table><thead><tr><th width="300">Tag</th><th width="74">Len</th><th width="124.66668701171875">Value / Description</th><th width="76.33331298828125">Typ</th><th width="78.33331298828125">Req</th><th width="94.33331298828125">Default</th></tr></thead><tbody><tr><td>Beginning of any wrappers, at minimum including <a href="https://magtek.gitbook.io/magtek-pilot-gitbooks/internal-documentation/index/3.0-messages-requests-responses-notifications-and-files/3.3-message-structure#response-message">Response Message</a></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>1008 = Command 0x1008 - Cancel Transaction</td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>No parameters.</td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>End of any wrappers, at minimum including <a href="https://magtek.gitbook.io/magtek-pilot-gitbooks/internal-documentation/index/3.0-messages-requests-responses-notifications-and-files/3.3-message-structure#response-message">Response Message</a></td><td></td><td></td><td></td><td></td><td></td></tr></tbody></table>

## Table - Request Example

Example (Hex)

```hex
AA 00 81 04 01 13 10 08 84 02 10 08
```

## Table - Response Example

Example (Hex)

```hex
AA 00 81 04 82 13 10 08 82 04 00 00 00 00
```


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