> 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/~/revisions/aurjDoOhAcnQLHeoR1ks/card-readers/mms-dyna-devices/emv-common-kernel/dynaflex-ii-go/documents/developers-manuals/programmers-manual-commands/commands/security/change-device-lock-passcode.md).

# Change Device Lock Passcode

## Command 0xEF07 – Change Device Lock Passcode

The host can use this command to change the device’s lock passcode. The value of the device lock passcode is stored in non-volatile memory so changes made to it will persist after the device is reset or power cycled. To change the device lock passcode using MagTek security or to see its default value see **Property 1.2.5.2.1.3 Device Lock Passcode**. See **Device Lock Feature** for more information.

## Table - Request Data for Command 0xEF07 – Change Device Lock Passcode

<table><thead><tr><th width="204.3333740234375">Tag</th><th width="75.33331298828125">Len</th><th width="254.66668701171875">Value / Description</th><th width="74.33331298828125">Typ</th><th width="75.6666259765625">Req</th><th width="98.6666259765625">Default</th></tr></thead><tbody><tr><td>Beginning of any wrappers, at minimum including <strong>Request Message</strong> </td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>EF07 = Command <strong>0xEF07 – Change Device Lock Passcode</strong></td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>81</td><td>4–63</td><td>Current Passcode. The current passcode in the clear. This must match the value of the current passcode or the command will fail.</td><td>B</td><td>M</td><td></td></tr><tr><td>82</td><td>04–63</td><td>New Passcode. The new passcode in the clear. It can only contain printable ASCII characters or the command will fail.</td><td>B</td><td>M</td><td></td></tr><tr><td>End of any wrappers, at minimum including <strong>Request Message</strong> </td><td></td><td></td><td></td><td></td><td></td></tr></tbody></table>

## Table - Response Data for Command 0xEF07 – Change Device Lock Passcode

<table><thead><tr><th width="260">Tag</th><th width="72.6666259765625">Len</th><th>Value / Description</th><th width="81.6666259765625">Typ</th><th width="75">Req</th><th width="98.666748046875">Default</th></tr></thead><tbody><tr><td>Beginning of any wrappers, at minimum including <strong>Response Message</strong> </td><td></td><td></td><td></td><td></td><td></td></tr><tr><td>EF07 = Command <strong>0xEF07 – Change Device Lock Passcode</strong></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 <strong>Response Message</strong> </td><td></td><td></td><td></td><td></td><td></td></tr></tbody></table>

## Table - Request example

{% code title="Example (Hex)" %}

```
AA00 81 04 0155EF07 84 0E EF07 810434333231 820434333231
```

{% endcode %}

## Table - Response example&#x20;

{% code title="Example (Hex)" %}

```
AA00 81048255EF07 820400000000 8402EF07
```

{% endcode %}


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