Packet loss in TCP

[venkateshdhara]

Answers checklist.

• I have read the documentation ESP-AT Programming Guide and the issue is not addressed there.
• I have used the latest released firmware or have updated my ESP-AT branch (master or release) to the latest version and checked that the issue is present there.
• I have searched the issue tracker for a similar issue and not found a similar issue.

General issue report

I am using ESP32-C3 and experiencing packet loss in reception in TCP and transmit is always good, following methods are debugged
system is setup in such a way ESP32 is connected to stm32l4 MCU and exchanging data every 5seconds with raspberry pi
1.Ran TCPDUMP service in RPI there is no tcp retransmission request observed.
2.ESP32 using in UART 115200 tried changing baud rate 230400.
3.Tried CIPRECTYPE=1. passive mode
4.probed logic analyzer on UART and confirmed data was not received on UART.
5.KEEPALIVE value 3 sec
6.used quick configuration to increase throughput as suggested in FAQ page
https://docs.espressif.com/projects/esp-at/en/latest/esp32/Compile_and_Develop/How_to_optimize_throughput.html#simple-quick-configuration

[ustccw]

You mentioned there is no tcp retransmission, and i assume your STM32L4 is good, the packet loss should happen on the UART transmission.
Could you please enable the uart hardware flow control by adding CTS/RTS line here, and enables it by sending AT+UART_CUR=230400,8,1,0,3