hey.
I faced an issue when using BufferedSerial class specially when writing buffer or data, it just write 2 data and stop ??, actually it is blocking and stuck.

here's the code

#include <Arduino.h>
#include "mbed.h"
rtos::Thread thread_1;
static mbed::BufferedSerial serial_port(p4, p5);
void uart_thread()
{
 serial_port.set_baud(115200);
 serial_port.write("buffer", 7); // never write all of 
 serial_port.write("9", 1);
 char buf[32] = {0};
 while (1)
 {
 if (uint32_t num = serial_port.read(buf, sizeof(buf)))
 {
 serial_port.write(buf, num);
 }
 }
}
void setup()
{
 thread_1.start(uart_thread);
}

I read Serial source code and I noticed it depends on UnbufferedSerial, I tested UnbufferedSerial and it worked as I expected but BufferedSerial's write functionally doesn't work well !

I used PlatformIO and Raspberry Pi Pico which is based on RP2040, so I hope the issue resolve as soon as possible and thanks 😁