# Data Link Module

{% hint style="danger" %}
The Microhard Data Link is not for sale anymore.

This page contains the relevant documentation for existing Microhard Data Links deployed in the field.
{% endhint %}

{% hint style="info" %}
The Data Link Module is designed to evaluate the **Microhard pMDDL2450** radio as a telemetry, control and video link. Other Microhard radios may work similarly, but are not officially supported by the Auterion Pairing Manager at this time.
{% endhint %}

<img src="https://3329189600-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FFW1Ge1p1f6WHyiYCb146%2Fuploads%2Fgit-blob-fe2948ce1d82964b1794cb99bd49216585f76802%2FPXL_20210618_133825478%20(1).jpg?alt=media" alt="" data-size="original">

![](https://3329189600-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FFW1Ge1p1f6WHyiYCb146%2Fuploads%2Fgit-blob-899a14288777b90681886e5f3ff01246b9bdc0a6%2FMH%20Carrier%20Interface%20Function%20Map.png?alt=media)

{% file src="<https://3329189600-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FFW1Ge1p1f6WHyiYCb146%2Fuploads%2Fgit-blob-2ccde2f6a36987b68f64df718df8cb850fa52a57%2FData-Link-Module.stl?alt=media>" %}
3D model
{% endfile %}

{% file src="<https://3329189600-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FFW1Ge1p1f6WHyiYCb146%2Fuploads%2Fgit-blob-500059de0331425d9416cf178a3f4032c34e7d0c%2FData-Link-Mechanical-drawing.pdf?alt=media>" %}
Mechanical drawing
{% endfile %}

## Connectors

<table data-header-hidden><thead><tr><th width="150">ID</th><th width="150">Name</th><th>Connector</th><th>Description</th></tr></thead><tbody><tr><td>ID</td><td>Name</td><td>Connector</td><td>Description</td></tr><tr><td>J1</td><td>USB</td><td>USB Type-C</td><td>pMDDL USB interface (pins 18 and 19)</td></tr><tr><td>J2</td><td>Ethernet</td><td><p>JST GH 4-pin</p><p>SM04B-GHS-TB</p></td><td>pMDDL LAN interface (pins 55 to 58), 100Base-T</td></tr><tr><td>J3</td><td>UART</td><td><p>JST GH 6-pin</p><p>SM06B-GHS-TB</p></td><td>pMDDL Serial interface (pins 28, 29, 31 and 34)</td></tr><tr><td>J51</td><td>POWER</td><td>Molex Micro-Fit 3.0<br>0436500210</td><td>Power supply input, 6.4V - 30V</td></tr><tr><td></td><td>Antenna</td><td>RP-SMA</td><td></td></tr><tr><td></td><td>Fan</td><td>JST GH 2-pin</td><td>5V connector to attach a fan for cooling</td></tr></tbody></table>

## Pinouts

### USB (J1)

Please refer to the official pinout specification for USB Type-C connectors. The connector supports USB High-Speed (up to 480 MBit/s) data rates.

### Ethernet (J2)

{% hint style="info" %}
This interface supports 100Base-T ethernet which can carry speeds up to 100MBit/s
{% endhint %}

<table data-header-hidden><thead><tr><th width="150">Pin</th><th width="150">Name</th><th>Dir</th><th width="150">Lvl</th><th>Function</th></tr></thead><tbody><tr><td>Pin</td><td>Name</td><td>Dir</td><td>Lvl</td><td>Function</td></tr><tr><td>1</td><td>ETH_TD_P</td><td>OUT</td><td>3.3V</td><td>Transmit + (Diff.)</td></tr><tr><td>2</td><td>ETH_TD_N</td><td>OUT</td><td>3.3V</td><td>Transmit - (Diff.)</td></tr><tr><td>3</td><td>ETH_RD_P</td><td>IN</td><td>3.3V</td><td>Receive + (Diff.)</td></tr><tr><td>4</td><td>ETH_RD_N</td><td>IN</td><td>3.3V</td><td>Receive - (Diff.)</td></tr></tbody></table>

#### UART (J3)

<table data-header-hidden><thead><tr><th width="150">Pin</th><th width="150">Name</th><th width="150">Dir</th><th width="150">Lvl</th><th>Function</th></tr></thead><tbody><tr><td>Pin</td><td>Name</td><td>Dir</td><td>Lvl</td><td>Function</td></tr><tr><td>1</td><td>NC</td><td></td><td></td><td>Not connected</td></tr><tr><td>2</td><td>RXD</td><td>IN</td><td>3.3V</td><td>pMDDL RXD</td></tr><tr><td>3</td><td>TXD</td><td>OUT</td><td>3.3V</td><td>pMDDL TXD</td></tr><tr><td>4</td><td>RTS</td><td>IN</td><td>3.3V</td><td>pMDDL RTS</td></tr><tr><td>5</td><td>CTS</td><td>OUT</td><td>3.3V</td><td>pMDDL CTS</td></tr><tr><td>6</td><td>GND</td><td></td><td></td><td>Ground</td></tr></tbody></table>

### Power (J51)

<table data-header-hidden><thead><tr><th width="150">Pin</th><th width="150">Name</th><th width="150">Dir</th><th width="150">Lvl</th><th>Function</th></tr></thead><tbody><tr><td>Pin</td><td>Name</td><td>Dir</td><td>Lvl</td><td>Function</td></tr><tr><td>1</td><td>GND</td><td></td><td></td><td>Ground</td></tr><tr><td>2</td><td>VIN</td><td></td><td>6.4V - 30V</td><td>Power Input</td></tr></tbody></table>

## Recovery Procedure

{% hint style="warning" %}
The radio modules included in the Skynode Evaluation Kit are already configured and in a pre-paired state, no further configuration is required. The following steps can be used to recover the factory pre-paired state or to configure a set of Microhard modules that is not already setup.
{% endhint %}

### Loading default pre-paired configuration

{% hint style="info" %}
After completing the recovery procedure below, the password to the Microhard's web interface will be "**auterionfct**".
{% endhint %}

1. Connect the radio module to your computer or laptop following the [wiring diagram](#wiring-during-configuration) below and power on the module. Even when you need to recover both radio modules, connect only one of them at a time and repeat this procedure afterwards for the other module.
2. Reset the radio module to factory defaults following the instructions under [Factory Reset](#factory-reset).
3. Verify that the Ethernet port of the computer or laptop is configured as a DHCP client.
4. Wait until the Ethernet connection is established and an IP address has been assigned.
5. Open your internet browser and navigate to the following URL: [http://192.168.168.1/](http://192.168.168.1/cgi-bin/webif/system-info.sh). This connects to the radio module's local web interface. The default login is\
   **Username: admin**\
   **Password: admin**
6. After logging in change the admin password as requested. This password will be overwritten again when we load the configuration file in the next step.
7. For your convenience we are providing configuration files for the Microhard Radios. Download the [configuration files](#configuration-files). The archive contains two configuration files, one for the AIR unit and one for the GROUND unit. The *AIR* unit is the module that is typically connected to Skynode, and the *GROUND* unit is typically connected to your desktop computer or laptop.
8. In the Microhard web interface, navigate to **System > Maintenance** and under **Restore Configuration** click **Choose File**. Select the correct configuration file from the previously downloaded archive and upload it.
9. Click on **Check Configuration File.**
10. After the configuration has been verified successfully click **Restore** and wait until the update is complete. This step also changes the configuration password to "**auterionfct**". You **must** change it back to "**admin**", even if the configuration GUI complains about it.\ <img src="https://3329189600-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FFW1Ge1p1f6WHyiYCb146%2Fuploads%2Fgit-blob-bee6962083cba28dd6312c687492f2a9ad76b225%2FScreenshot%20from%202021-04-30%2018-50-02.png?alt=media" alt="" data-size="original">
11. Repeat the same process for the second unit. pairing will only work if both *AIR* and *GROUND* unit have their respective configuration loaded!

### Configuration Files

{% file src="<https://3329189600-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FFW1Ge1p1f6WHyiYCb146%2Fuploads%2Fgit-blob-4edd5488fd5babf1da712681e8f1dcc27d8ac95a%2FMicrohardpMDDL2450-PRE-PAIRED-PW-auterionfct.zip?alt=media>" %}
Microhard pMDDL2450 pre-paired configs
{% endfile %}

### Wiring during Configuration

![](https://3329189600-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FFW1Ge1p1f6WHyiYCb146%2Fuploads%2Fgit-blob-0d9c3ecee380fb1a5272b24a35de600661ab5630%2FMicrohard%20Wiring%20Ground%20\(2\).png?alt=media)

### Factory Reset

{% hint style="warning" %}
The modules have to be configured as *AIR* and *GROUND* unit afterwards. One method for doing so is [explained above](#recovery-procedure).
{% endhint %}

1. Power the Microhard using the power module and the wall power supply or a battery.
2. Wait until the Microhard is fully booted. Booting takes about 60-75 seconds, and is complete when the three RSSI LEDs (D7,D8 and D9) indicated below start lighting up in a "walking sequence" (i.e. LEDs are active one after another, in a continuous cycle).\ <img src="https://3329189600-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FFW1Ge1p1f6WHyiYCb146%2Fuploads%2Fgit-blob-159ffa6b69245424c338f2e6bb76d700f8745550%2FMH%20Carrier%20Interface%20Function%20Map-highlight-rssi.png?alt=media" alt="" data-size="original"> ![](https://3329189600-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FFW1Ge1p1f6WHyiYCb146%2Fuploads%2Fgit-blob-b3e2cce89af7f5dd3a74b9aa0e8eabb25cee883a%2Fmh-led-detail.png?alt=media)​
3. Press and hold the **Config Button** by inserting a pointy tool such as a paper clip. Once the CPU Status LED begins to flash, keep pressing the button for more than 10s. The module will reboot after you release the button, this takes again about 60-75 seconds.\ <img src="https://3329189600-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FFW1Ge1p1f6WHyiYCb146%2Fuploads%2Fgit-blob-0ab3601e803d629dc6f16795dd9994080691e341%2FMH%20Carrier%20Interface%20Function%20Map-highlight-config.png?alt=media" alt="" data-size="original"> ​\
   The module is now reset and can be configured for the use with Skynode. You **must** configure it to be an *AIR* or *GROUND* unit now by [loading the configs](#loading-default-pre-paired-configuration) prior to being able to use it.

##