Arm Mbed OS support forum

Store a text file in PC from MAX3265PICO platform

Hello All,
I have recently started working on Mbed OS .

  1. Board -MAX365PICO
  2. OS - Windows10

I have successfully run the LED blinking and other simple GPIO handling programs successfully. Now I am writing a simple program where I have to store values of arrays (integer) in text file. I have checked the FATFILESYSTEM example program. When I execute the code, I could not find the file which I have created in the code.
Someone can help me to explain how I can write the array data into text file and save it on PC.

Thanks and regards,


maybe this will help - Read data from txt file (nucleo F401RE) - Mbed OS - Arm Mbed OS support forum

BR, Jan

Hi @gnss007 as i understand you can’t read or write to the local file system, only a couple of old legacy boards can do it, you will want to be writing to an SD card or USB stick or similar

I hope this can help

From my point of view, the keyword local is every time in the context of current device. So when we talk about PC (memory), the local can be PC’s C drive. But when we talk about a Mbed device the local can be onchip flash memory and PC is a host.

I your case you tried to read/write a file to the host’s (PC) file system but that is not possible. You can not write to or read from PC’s file system over USB directly.

  • You can send data from Mbed device to a host over UART with TTL convertor or via USB interface (it depends on the equipment of the board - USB, BLE, ETH, WIFI, etc. ) but on host side is must running an app or a driver what will listen what your board is sending and then the app can store received data into the host’s file system. Of course, the Mbed device must be permanently connected to the host.
  • Another alternative can be use one of BlockDevices, for example SDBlockDevice with FATFileSystem. You will transfer the SD card between PC and Mbed board by hands but it is stand alone device.
    Theoretically you can try to make a program with APIs above and USBMSD. That is something similar what was provided by the old LocalFileSystem, I think.

Here is descripted how it was done in the past - LocalFileSystem - Handbook | Mbed

BR, Jan