# CAN Termination Resistance Software Toggle

## Currently supported model and serial number

<table data-header-hidden><thead><tr><th>Model Name</th><th width="456.39990234375">Serial Number</th></tr></thead><tbody><tr><td>H-Flow</td><td>All version </td></tr><tr><td>DLVR Airspeed Sensor</td><td>19012<mark style="color:red;">001</mark>***; 19013<mark style="color:red;">001</mark>***; 19014<mark style="color:red;">001</mark>*** and later</td></tr><tr><td>PM08-CAN</td><td>15028<mark style="color:red;">001</mark>***; 15029<mark style="color:red;">001</mark>***; 15030<mark style="color:red;">001</mark>*** and later</td></tr><tr><td>DroneCAN M9N</td><td>12032<mark style="color:red;">002</mark>*** and later</td></tr><tr><td>DroneCAN H-RTK F9P Helical</td><td>12037<mark style="color:red;">003</mark>*** and later</td></tr><tr><td>DroneCAN RM3100</td><td>18088<mark style="color:red;">002</mark>***; 18089<mark style="color:red;">002</mark>*** and later</td></tr><tr><td>H-RTK ZED-F9P Rover</td><td>12059<mark style="color:red;">002</mark>*** and later</td></tr></tbody></table>

## Ardupilot (Mission Planner) setup guide

1. Connect the DroneCAN peripheral to the CAN port on the flight controller
2. After establishing the connection to the flight controller on MissionPlanner, head to Setup->Optional Hardware->DroneCAN/UAVCAN. Click MAVlink-CAN1 if connected to the CAN1 port and MAVlink-CAN2 for the CAN2 port to scan CAN devices.
3. Find the appropriate device (Holybro products have HolybroG4 in the name), click menu->Parameters:

   <figure><img src="https://2367252986-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FLIgtGDAvVGkCKGOJb1bR%2Fuploads%2FtjNtk8ckanrBPKvzNvTd%2Fimage.png?alt=media&#x26;token=398eb737-5c96-4b0a-8b74-46b16597b20d" alt=""><figcaption></figcaption></figure>
4. Find the CAN\_TERMINATE command and you will see the value defaults to 0. Set CAN\_TERMINATE to 1 to enable 120Ω termination resistance, and 0 to disable it

<figure><img src="https://2367252986-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FLIgtGDAvVGkCKGOJb1bR%2Fuploads%2Fuua805CTSNZSm61lG1iY%2Fimage.png?alt=media&#x26;token=0d47edd0-03af-41d8-bb34-1cd506e59a92" alt=""><figcaption></figcaption></figure>

5. Click Write Params to save the configuration

## PX4 (QGroundControl) setup guide

1. Make sure the parameters are set accordingly so the firmware can detect the CAN device
2. Navigate to Vehicle Setup->Parameters and click Standard to hide flight controller parameters:

   <figure><img src="https://2367252986-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FLIgtGDAvVGkCKGOJb1bR%2Fuploads%2FR2KQbFH9Jkfa4cDwDeXO%2Fimage.png?alt=media&#x26;token=77aad1ed-aecf-42a4-8818-8ff5eb67eae1" alt=""><figcaption></figcaption></figure>
3. If your CAN device is successfully detected, you will see a section labeled Components with numbers following it:

   <figure><img src="https://2367252986-files.gitbook.io/~/files/v0/b/gitbook-x-prod.appspot.com/o/spaces%2FLIgtGDAvVGkCKGOJb1bR%2Fuploads%2FQFDsVCF25hbh4Nx5eMjH%2Fimage.png?alt=media&#x26;token=1b717c35-edfd-45a1-a468-b2f32f3a1be3" alt=""><figcaption></figcaption></figure>
4. Expand the Component section, navigate to the CAN tab, and change the CAN\_TERMINATE value to enable or disable termination resistance (120Ω). Set to 1 to enable and 0 to disable.


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