# bear2305/x86-assemby-fat12 architecture

> Architecture diagram of the GitHub repository bear2305/x86-assemby-fat12, generated by GitDiagram from its file tree, README and a sample of source files (last updated 2026-09-26). It is an AI-made overview: check details against the source.

- Interactive diagram: https://gitdiagram.com/bear2305/x86-assemby-fat12
- Repository: https://github.com/bear2305/x86-assemby-fat12

## Overview

This repository is a single-file, 16-bit x86 FAT12 boot-sector example for legacy BIOS systems. Its documented runtime path is BIOS loading the sector, execution reaching an entry point that halts the processor, and disk tools or operating systems recognizing the volume from its BPB. The README describes these behaviors, but no assembly source excerpt was available to verify further control flow.

Main entry points: [`FAT12.asm`](https://github.com/bear2305/x86-assemby-fat12/blob/main/FAT12.asm) (FAT12 Boot Sector)

## Diagram (Mermaid)

```mermaid
flowchart TD

node_bios(("Legacy BIOS"))
node_boot_sector["FAT12 Boot Sector<br/>[FAT12.asm]"]
node_bpb["FAT12 BPB<br/>[FAT12.asm]"]
node_entry["Entry Point<br/>[FAT12.asm]"]
node_cpu(("Processor"))
node_disk_tools(("Disk Tools / OS"))

node_bios -->|"loads sector"| node_boot_sector
node_boot_sector -->|"jumps to"| node_entry
node_entry -->|"halts"| node_cpu
node_disk_tools -->|"recognizes volume"| node_bpb

click node_boot_sector "https://github.com/bear2305/x86-assemby-fat12/blob/main/FAT12.asm"
click node_bpb "https://github.com/bear2305/x86-assemby-fat12/blob/main/FAT12.asm"
click node_entry "https://github.com/bear2305/x86-assemby-fat12/blob/main/FAT12.asm"

classDef toneNeutral fill:#f8fafc,stroke:#334155,stroke-width:1.5px,color:#0f172a
classDef toneBlue fill:#dbeafe,stroke:#2563eb,stroke-width:1.5px,color:#172554
classDef toneAmber fill:#fef3c7,stroke:#d97706,stroke-width:1.5px,color:#78350f
classDef toneMint fill:#dcfce7,stroke:#16a34a,stroke-width:1.5px,color:#14532d
classDef toneRose fill:#ffe4e6,stroke:#e11d48,stroke-width:1.5px,color:#881337
classDef toneIndigo fill:#e0e7ff,stroke:#4f46e5,stroke-width:1.5px,color:#312e81
classDef toneTeal fill:#ccfbf1,stroke:#0f766e,stroke-width:1.5px,color:#134e4a
class node_bios,node_cpu,node_disk_tools toneIndigo
class node_boot_sector,node_bpb,node_entry toneTeal
```

## Components

### Other components

- **Legacy BIOS**
- [FAT12 Boot Sector](https://github.com/bear2305/x86-assemby-fat12/blob/main/FAT12.asm): `FAT12.asm`
- [FAT12 BPB](https://github.com/bear2305/x86-assemby-fat12/blob/main/FAT12.asm): `FAT12.asm`
- [Entry Point](https://github.com/bear2305/x86-assemby-fat12/blob/main/FAT12.asm): `FAT12.asm`
- **Processor**
- **Disk Tools / OS**

## Connections

- Legacy BIOS → FAT12 Boot Sector: loads sector
- FAT12 Boot Sector → Entry Point: jumps to
- Entry Point → Processor: halts
- Disk Tools / OS → FAT12 BPB: recognizes volume