Hi @mercala_eng ,
You can check the example sketches available in Arduino IDE > Examples:
- PortentaSDCARD > TESTSDCARD: ArduinoCore-mbed/libraries/Portenta_SDCARD/examples/TestSDCARD/TestSDCARD.ino at main · arduino/ArduinoCore-mbed · GitHub
- Arduino_POSIXStorage > SD_Card_Example: Arduino_POSIXStorage/examples/SD_Card_Example/SD_Card_Example.ino at main · arduino-libraries/Arduino_POSIXStorage · GitHub
Best,