Transmit a .txt file between 2 microcontrollers?

Hi there,

I have some very (!) limited experience of using Keil uVision with an ST STM32 Nucleo-32 STM32L432KC development board. In the past I've written some "dummy" data, in the form of a series of decimal numbers, to a variable and then transmitted that using the UART Tx pin. That's more or less the extent of my experience.

What I'd like to do now is transmit a .txt file from one PC to another, via two of those microcontrollers and their serial pins:

1) read a .TXT file saved on a (Windows) PC that the Transmitting micro-controller is connected to.

2) transmit this data using the serial UART pin.

I guess steps 1) & 2) would require converting the ASCII characters to binary bits...

3) At the Receiver micro-controller, I'd like to read this serial data, convert it back into text and finally...

4) Save the received text as a .TXT file.

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By the way, the .txt files could be relatively large (e.g. 5 Mb) so I may not be able to store all the received data in memory before dumping it to the .txt file.

Is this something that is possible to do using uVision? If so, would anyone be able to give some pointers on how to read and write .txt files?

Many thanks in advance and apologies if my question is too vague or off-topic for these forums.

Jonathan