Issue while increasing the data size more than 495 Bytes for Best-effort stream

[SiddharthZokarkar]

• Hardware description: ESP32
• RTOS: FreeRTOS
• Installation type: micro_ros_setup
• Version: micro-ROS running on ROS2 Foxy

Hello

I am using best-effort stream communication for publisher and subscriber.

The publisher and subscriber are working fine for data upto 495 Bytes.

But after increasing the data over 495 Bytes, the publisher is not publishing the topic data (although it is showing the published topic name in ros2 topic list) and the subscriber is showing a serialization error as shown in the below picture.

app-colcon.meta

I am not able to understand the problem . It will be great if anyone can help me to figure out the problem.

Thank you very much!!

[SiddharthZokarkar]

Hello @pablogs9 ,

I am struggling to increase the data length using Best-effort stream over 495 Bytes. Is that a limit ? Or is there any way to increase the size?

Kindly give your suggestions. Thank you so much.

[Acuadros95]

Hi @SiddharthZokarkar,

In this case the transport used is custom, as the provided configurations (udp, serial, ...) are used only for linux builds. Rebuild your micro-ROS library using the following configuration parameter: UCLIENT_PROFILE_CUSTOM_TRANSPORT

[SiddharthZokarkar]

Hello @Acuadros95 ,

Thanks for the reply. I am using inbuild Serial transport on a Linux system instead of a custom transport.
What is the procedure to increase the data size more than 495 Bytes?

I tried by changing UCLIENT_SERIAL_TRANSPORT_MTU 4096 but it is not working.

Kindly guide me. Thanks

[Acuadros95]

I tried by changing UCLIENT_SERIAL_TRANSPORT_MTU 4096 but it is not working.

You need to use the UCLIENT_PROFILE_CUSTOM_TRANSPORT parameter instead of the Serial one.

[SiddharthZokarkar]

Ok thank you so much!!