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Issue with Command Handling in AVR128DA48 UART Communication

I am using AVR128DA48 microcontroller to control an LED in serial communication. The way I set it up is not complex;
I’m sending *‘ON’* and *‘OFF’* commands from a `python` script over `UART` to toggle the LED on the microcontroller. Funny how I am encountering an issue where the *first command is ignored*, but the second one triggers a response.

Here’s what happens:
– I send *‘ON’* – the microcontroller does *not respond*.
– I send *‘OFF’* – it responds with *‘LED ON’*.
– I send *‘ON’* again !! – it responds with *‘LED OFF’*.

It makes me feel like the board is always responding to the *previous* command, and I don’t know why 🥲.

Normally I know microcontroller has simple firmware that reads serial data, processes the *‘ON’* or *‘OFF’* commands, toggles the LED accordingly, and sends back a confirmation message like *‘LED ON’* or *‘LED OFF’*.

But what could be causing the *delay or missed first command* that I am facing?

How can I ensure that the board processes the *first command correctly* and responds immediately?

I made sure to verifying the baud rate and ensuring it matches on both ends as 9600

Even flushing the serial buffer before and after sending commands in the python script.

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