> For the complete documentation index, see [llms.txt](https://docs.verifone.com/llms.txt). Markdown versions of documentation pages are available by appending `.md` to page URLs; this page is available as [Markdown](https://docs.verifone.com/support-us/verifone-hq/vhq-parameter-management/configuring-parameter-templates/parameter-synchronization-download-to-devices.md).

# Parameter synchronization (download) to devices

Download and synchronize parameters to devices in VHQ using automated downloads that evaluate parameter precedence, build parameter files in multiple formats, and verify synchronization status.

<details>

<summary>Keywords</summary>

Also called: parameter download, parameter sync. Search terms: management plan, ADKH, POINT format, synchronization status.

</details>

## What is parameter synchronization?

The **Downloads/Synchronize** phase evaluates and builds the list of parameters to download in the appropriate format. VHQ checks the parameters configured at the device level against the server, and if the matching criteria are met, synchronization takes place. If synchronization fails, VHQ prepares a package bundling the applications, parameter form view file, and parameter templates, and sends it to the device with the appropriate GID.

Once parameters are configured and saved (or activated), VHQ evaluates, builds, and downloads a parameter file containing the parameters and their values, in a format based on the parameter definition file.

{% hint style="info" %}
VHQ supports parameter downloads only through automated downloads.
{% endhint %}

## Evaluating parameters and their values

VHQ builds and downloads parameters using the following order of precedence:

1. Parameter values configured at the device level.
2. Parameter values configured for parameter templates (PT).
3. Default parameter values as defined in PDX.

A device-level value always takes precedence; if none is configured, the PT value applies; if neither is configured, the PDX default applies.

## Identifying the parameter change set

As part of automated downloads, VHQ detects when a software update is required and sends the download instructions (the management plan) to the device, which then downloads the updates. Every software update also includes instructions to download all parameters for the applications in that update.

The device confirms successful download and application of parameters — VHQ records this as the synchronized date. When a user later configures or edits parameters and saves (or activates) the changes, VHQ records this as the activation date. Parameters with an activation date later than the synchronized date are identified as changed parameters.

## Building the parameter file

VHQ builds a parameter file for download, containing either only changed parameters or all parameters, depending on what the application/OS can consume. The format and content are determined by the *Parameter File* > *Format* value in the Parameter Definition File:

* **Config.sys** and **Config.$$$** formats are compressed into a .ZIP file, with one folder per GID.
* **ADKH** format files are built per the structure in *Parameter File* > *OutFileFormat*.

Supported download formats are POINT, ADKH, ADK-INF, CONFIG$$$, and CONFIGSYS. ADK-INF, the newer ADK Info Svc Import/Export format, supersedes all other ADK formats — it uses a structured, fully-pathed format compatible with both SQLite (relational) and properties-db (hierarchical) database types, rather than the simpler compound-name format properties-db alone supported.

## Download and verify

VHQ prepares download instructions for the parameter files. For example, if a package has 2 applications, each with 2 parameter files, the management plan includes instructions to download:

* The software package.
* Parameter File #1 and #2 for Application #1.
* Parameter File #1 and #2 for Application #2.

The device processes the instructions, downloads each file, applies the parameters, and reports status. VHQ updates the synchronization status accordingly — you can view the sync status per application and the detailed status per parameter file.


---

# Agent Instructions
This documentation is published with GitBook. GitBook is the documentation platform designed so that both humans and AI agents can read, navigate, and reason over technical content effectively. Learn more at gitbook.com.

## Querying This Documentation
If you need additional information that is not directly available in this page, you can query the documentation dynamically by asking a question.

Perform an HTTP GET request on the current page URL with the `ask` query parameter, and the optional `goal` query parameter:

```
GET https://docs.verifone.com/support-us/verifone-hq/vhq-parameter-management/configuring-parameter-templates/parameter-synchronization-download-to-devices.md?ask=<question>&goal=<endgoal>
```

`ask` is the immediate question: it should be specific, self-contained, and written in natural language.
`goal` is optional and describes the broader end goal you are ultimately trying to accomplish on behalf of the user. GitBook uses it to tailor the answer towards what is most useful for that goal.

The response will contain a direct answer to the question and relevant excerpts and sources from the documentation.

Use this mechanism when the answer is not explicitly present in the current page, you need clarification or additional context, or you want to retrieve related documentation sections.