# Help with RoboMaster TT ESP32 Custom Commands

**URL:** <https://community.droneblocks.io/t/help-with-robomaster-tt-esp32-custom-commands/445>\
**Category:** Tello Coding\
**Created:** [June 30, 2022, 6:12pm UTC](https://community.droneblocks.io/t/help-with-robomaster-tt-esp32-custom-commands/445 "2022-06-30T18:12:19Z")\
**Posts on this page:** 3\
**Page:** 1

<div class="post-metadata">

**Author:** ![dbaldwin](https://avatars.discourse-cdn.com/v4/letter/d/d2c977/32.png) [@dbaldwin](https://community.droneblocks.io/u/dbaldwin)\
**Post date:** [June 30, 2022, 6:12pm UTC](https://community.droneblocks.io/t/help-with-robomaster-tt-esp32-custom-commands/445/1 "2022-06-30T18:12:19Z")

</div>

I’m trying to use the RMTT ESP32 Arduno code to support custom commands. In DroneBlocks we want to introduce some new blocks that allow users to add sensors to their expansion module and take readings. In the Arduino firmware there is a custom\_callback function for DIY commands specified here:

> <https://github.com/dbaldwin/RMTT_Libs/blob/master/examples/default/default.ino#L1130-L1140>

How do we invoke this callback? I’ve tried to send several different commands with a Serial.print inside of this callback but cannot get it to work. Any help would be appreciated. Thanks in advance.

---

<div class="post-metadata">

**Author:** ![ussa](https://avatars.discourse-cdn.com/v4/letter/u/58956e/32.png) [@ussa](https://community.droneblocks.io/u/ussa)\
**Post date:** [July 1, 2022, 4:13am UTC](https://community.droneblocks.io/t/help-with-robomaster-tt-esp32-custom-commands/445/2 "2022-07-01T04:13:41Z")

</div>

this callback is used to receive custom udp text command.  
you should send “EXT DIY xxxx(e.g. measure)” to TT by UDP port，then parsing this text cmd in cuestom\_callback() like led\_callback().

---

<div class="post-metadata">

**Author:** ![dbaldwin](https://avatars.discourse-cdn.com/v4/letter/d/d2c977/32.png) [@dbaldwin](https://community.droneblocks.io/u/dbaldwin)\
**Post date:** [July 1, 2022, 1:55pm UTC](https://community.droneblocks.io/t/help-with-robomaster-tt-esp32-custom-commands/445/3 "2022-07-01T13:55:36Z")

</div>

This works perfectly! I did not think to use EXT in front of the DIY command. Thanks for the information and I’ll share more details about my project soon.