ESP32 + rosserial_python over WiFi: Lost sync with device

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Hi,

I am trying to establish rosserial communication between ESP32 (using ESP-IDF and not Arduino framework) and host Ubuntu machine. Here is my implementation: https://github.com/sachin0x18/rosseri...

I am using ROS Kinetic and Ubuntu 16.04. rosserial_python version is 0.7.7 (as per package.xml).

I can establish communication over UART using rosrun rosserial_python serial_node.py and it can recognise publisher and subscriber topics.

When I establish communication over WiFi socket using rosrun rosserial_python serial_node.py tcp, rosserial_python on my Ubuntu machine can establish a connection and recognise the publisher and subscriber topics but after 15 seconds, it spits out Lost sync with device, restarting... and the same thing happens in a loop

[INFO] [1565188371.809821]: ROS Serial Python Node
Fork_server is:  False
[INFO] [1565188371.814939]: Waiting for socket connections on port 11411
waiting for socket connection
[INFO] [1565188380.808154]: Established a socket connection from 10.0.0.137 on port 49464
[INFO] [1565188380.809062]: calling startSerialClient
[INFO] [1565188382.986998]: Note: publish buffer size is 1024 bytes
[INFO] [1565188382.989866]: Setup publisher on chatter [std_msgs/String]
[ERROR] [1565188397.960632]: Lost sync with device, restarting...
[INFO] [1565188398.027021]: Setup publisher on chatter [std_msgs/String]
[ERROR] [1565188413.012285]: Lost sync with device, restarting...
[INFO] [1565188413.073520]: Setup publisher on chatter [std_msgs/String]

I am calling nh.spinOnce()every 1 second so it shouldn't be a problem of time sync failure. https://github.com/sachin0x18/rosseri...

For debug purpose, I have dumped the bytes that I receive and bytes that I transmit

I (3645) event: sta ip: 10.0.0.137, mask: 255.255.254.0, gw: 10.0.0.1                                          
I (3645) wifi station: got ip:10.0.0.137
I (3645) wifi station: Connected to AP
I (3735) wifi station: Successfully connected
Received at read: 0xff
Received at read: 0xfe
Received at read: 0x0
Received at read: 0x0
Received at read: 0xff
Received at read: 0x0
Received at read: 0x0
Received at read: 0xff
I (5955) rosserial: Sending message over ROS 16
I (5965) Sent buffer: ff fe 08 00 f7 0a 00 00  00 00 00 00 00 00 00 f5     |................|
I (5965) rosserial: Sending message over ROS 80
I (5975) Sent buffer: ff fe 48 00 b7 00 00 7d  00 07 00 00 00 63 68 61     |..H....}.....cha|
I (5985) Sent buffer: 74 74 65 72 0f 00 00 00  73 74 64 5f 6d 73 67 73     |tter....std_msgs|
I (5995) Sent buffer: 2f 53 74 72 69 6e 67 20  00 00 00 39 39 32 63 65     |/String ...992ce|
I (6005) Sent buffer: 38 61 31 36 38 37 63 65  63 38 63 38 62 64 38 38    |8a1687cec8c8bd88|
I (6015) Sent buffer: 33 65 63 37 33 63 61 34  31 64 31 00 04 00 00 21     |3ec73ca41d1....!|
I (7025) rosserial: Sending message over ROS 24
I (7025) Sent buffer: ff fe 10 00 ef 7d 00 0c  00 00 00 68 65 6c 6c 6f       |.....}.....hello ...