CircuitPython version and board name

Adafruit CircuitPython 9.2.7 on 2025-04-01; Adafruit Feather ESP32-S3 Reverse TFT with ESP32S3

Code/REPL

import board
import busio

uart = busio.UART(board.TX, board.RX, baudrate=1200)
#string being sent is "<AA>\n"

while True:
    line = uart.readline()
    if line:
        print("Received line:", line.decode().strip())
    num_bytes = uart.in_waiting
    if num_bytes > 0:
        print(f"{num_bytes} bytes waiting")
        data = uart.read(num_bytes)

Behavior

Code done running.

Press any key to enter the REPL. Use CTRL-D to reload.
soft reboot

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code.py output:
Received line:
115 bytes waiting
Received line:
115 bytes waiting
Received line:
115 bytes waiting
Received line:
115 bytes waiting

Description

When sending a test string "\n" at a rate 1 full string per 2 sec, nothing happens until the receive buffer is full (that's my assumption). Once the program is running, the first "Received line: " doesn't happen until the buffer reaches the 115 bytes. Then waits again for a period then prints the same thing again. As opposed the expected behavior of a single showing 5 bytes waiting. I've tried just a version using "uart.read(1)" with a similar result - that being it doesn't respond until the buffer is full.

Additional information

No response