Z80 Assembly 57: Disk and File System Access (Sectors, Tracks, and FAT)
The Challenge of Physical Storage When a user program requests to open a file (e.g., MYFILE.BIN), the OS kernel must translate that name into a list of physical disk addresses (sectors) where the data is stored. Key Disk Terminology: Track: A concentric ring on the disk where data is stored. Sector: A small, fixed-size block of data (e.g., 512 bytes) that lives on a track. Directory: A list of file names, sizes, and the starting sector number for each file. The File Allocation Table (FAT) The File Allocation Table (FAT) is the core data structure that links a file’s starting sector to all the subsequent sectors that make up the file. ...