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# 1.3 FAT File System Using NVM Media

This application shows an example of implementing a FAT disk in the device internal Flash memory.

## Description

### File System Operations on NVM

- Application places a FAT disk image consisting of a Master Boot Record (MBR) sector, Logical Boot Sector, File allocation Table, and Root Directory Area in the internal Flash memory (NVM)
- During execution, the application first opens an existing file named `FILE.txt` and performs following file system related operations:
  - SYS_FS_FileStat
  - SYS_FS_FileSize
  - SYS_FS_FileSeek
  - SYS_FS_FileEOF
- It tries to read the file and checks if string `Data` is present. If present it continues to next step or it fails the application.
- Finally, the string `Hello World` is written to this file. The string is then read and compared with the string that was written to the file. If the string compare is successful, an LED indication is provided.

### File System Layer Uses

- Memory driver to communicate with underlying NVM media

## Downloading and Building the Application

To clone or download this application from GitHub, go to the main page of this repository and then click Clone button to clone this repository or download as zip file. This content can also be downloaded using content manager by following these instructions.

Path of the application within the repository is apps/fs/nvm_fat/firmware.

To build the application, refer to the following table and open the project using its IDE.

Project Name | Description
--- | ---
pic32mk_gp_db.X | MPLAB X project for PIC32MK GP Development Kit
pic32mk_mcm_curiosity_pro.X | MPLAB X project for PIC32MK MCM Curiosity Pro Development Board
pic32mk_mca_curiosity_pro.X | MPLAB X project for PIC32MK MCA Curiosity Pro Development Board

## Setting Up the Hardware

The following table shows the target hardware for the application projects.

Project Name | Description
--- | ---
pic32mk_gp_db.X | PIC32MK GP Development Kit
pic32mk_mcm_curiosity_pro.X | PIC32MK MCM Curiosity Pro Development Board
pic32mk_mca_curiosity_pro.X | PIC32MK MCA Curiosity Pro Development Board

### Setting Up PIC32MK GP Development Kit

- Connect micro USB cable to the Debug USB connector (J12) on the board to the computer

### Setting Up PIC32MK MCM Curiosity Pro Development Board

- Connect a micro USB cable to the USB DEBUG port J500

### Setting Up PIC32MK MCA Curiosity Pro Development Board

- Connect a micro USB cable to the USB DEBUG port

## Running the Application

1. Build and program the application using its IDE.
2. Press Switch to start the file operations.
3. The LED is turned ON when the File `FILE.txt` has the app data `Hello World` written in it.

Refer to the following table for Switch and LED names:

Board | Switch Name | LED Name
--- | --- | ---
PIC32MK GP Development Kit | S1 | LED3
PIC32MK MCM Curiosity Pro Development Board | SW1 | LED2
PIC32MK MCA Curiosity Pro Development Board | SW200 | LED1

Rev: D