# Set Fixed LLH or ECEF

**This step-by-step tutorial will let you to manually set the Longitude, Latitude, Height and Earth-Centered Earth-Fixed for the Base.**

> **LLH**: Longitude, Latitude, Height
>
> **ECEF**: Earth-Centered Earth-Fixed

First, connect your GNSS device to a computer using a USB micro cable.

![](/files/-LdEnYZLwhXVFEwUuCNY)

Now start the U-blox “u-center” software. Then on the top left corner of the screen, left-click on the reversed tiny black triangle to select the COM Port related to your GNSS device. (the COM port may differ, COM7 as shown in pictures)

![](/files/-LYbIddBqnC-aXKJ1bxh)

Make sure the connection icon is blinking in the bottom state bar. It indicates that the serial communication between the computer and the GNSS device is working.

![](/files/-LYbHSKTiJZ0j0qAf-5e)

Next go to ‘View’ then click on “**Generation 9 Configuration View**”

![](/files/-LYbUsIAWEUg8JmCOVN6)

A new window showing by default “**GNSS Configuration**” opens.

1. So first, click on “**Advanced Configuration**” to display all the configuration registers.
2. Then click on the small ‘+’ on the **CFG-TPMODE** line
3. You can now have access to an expanded menu and click on **CFG-TPMODE-MODE**
4. Select “**2-FIXED**” in the dropdown menu
5. Click consecutively on **RAM**, **BBR** and **Flash** to write changes into RAM and both non-volatile memories (BBR and Flash)
6. Check the 3 corresponding commands are present in the “Ready to send” box and then click on ‘**Send**’

![](/files/-LYbizDK-0RpErknp_eD)

{% tabs %}
{% tab title="LLH: Longitude, Latitude, Height set up" %}

> Make sure to set up the base in Fixed Mode before setting up LLH mode

A new window showing by default “**GNSS Configuration**” opens.

1. So first, click on “**Advanced Configuration**” to display all the configuration registers.
2. Then click on the small ‘+’ on the **CFG-TPMODE** line
3. You can now have access to an expanded menu and click on **CFG-TPMODE-POS\_TYPE**
4. Select “**1-LLH**” in the dropdown menu
5. Click consecutively on **RAM**, **BBR** and **Flash** to write changes into RAM and both non-volatile memories (BBR and Flash)
6. Check the 3 corresponding commands are present in the “Ready to send” box and then click on ‘**Send**’

![](/files/-LYbjU4df099o-IsB71I)

#### Setting up the Longitude and Latitude

A new window showing by default “GNSS Configuration” opens.

1. So first, click on “**Advanced Configuration**” to display all the configuration registers.
2. Then click on the small ‘+’ on the **CFG-TPMODE** line
3. You can now have access to an expanded menu and click on **CFG-TPMODE-LAT**
4. Enter a valid degree value within a 1e-7 scale (ex : you want 45.9635687° = you write 459635687, if you want 01.9532443° = you write 019532443)
5. Click consecutively on **RAM**, **BBR** and **Flash** to write changes into RAM and both non-volatile memories (BBR and Flash)
6. Check the 3 corresponding commands are present in the “Ready to send” box and then click on ‘**Send**’

![](/files/-LYf1G7gwgnOalF84iqd)

> Repeat the same process to set CFG-TPMODE-LON value 
>
> Make sure to set up the base in Fixed & LLH mode before setting up LAT & LON

#### Setting up the Height

A new window showing by default “**GNSS Configuration**” opens.

1. So first, click on “**Advanced Configuration**” to display all the configuration registers.
2. Then click on the small ‘+’ on the **CFG-TPMODE** line
3. You can now have access to an expanded menu and click on **CFG-TPMODE-HEIGHT**
4. Enter a valid height value in cm (ex : you want 200m = you write 20’000)
5. Click consecutively on **RAM**, **BBR** and **Flash** to write changes into RAM and both non-volatile memories (BBR and Flash)
6. Check the 3 corresponding commands are present in the “Ready to send” box and then click on ‘**Send**’

![](/files/-LYf2FoeuHSgNGEi-695)

> Make sure to set up the base in Fixed & LLH mode before setting up HEIGHT

{% hint style="success" %}
You have successfully configured your GNSS device and can start using it !
{% endhint %}
{% endtab %}

{% tab title="ECEF: Earth-Centered Earth-Fixed set up" %}

> Make sure to set up the base in Fixed Mode before setting up ECEF mode

A new window showing by default “**GNSS Configuration**” opens.

1. So first, click on “**Advanced Configuration**” to display all the configuration registers.
2. Then click on the small ‘+’ on the **CFG-TPMODE** line
3. You can now have access to an expanded menu and click on **CFG-TPMODE-POS\_TYPE**
4. Select “**0-ECEF**” in the dropdown menu
5. Click consecutively on **RAM**, **BBR** and **Flash** to write changes into RAM and both non-volatile memories (BBR and Flash)
6. Check the 3 corresponding commands are present in the “Ready to send” box and then click on ‘**Send**’

![](/files/-LYf2lhrGdGsfoKjs_yr)

{% hint style="success" %}
You have successfully configured your GNSS device and can start using it !
{% endhint %}
{% endtab %}
{% endtabs %}


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