mirror of
https://github.com/alfishe/amiga-bootcamp.git
synced 2026-06-13 00:26:28 +00:00
docs(amiga): complete AmigaOS 3.1/3.2 developer reference — 172 files across 17 sections
Comprehensive technical documentation covering: - Hardware: OCS/ECS/AGA custom chip registers, Copper & Blitter deep dives - Boot sequence: cold boot through startup-sequence - Binary format: HUNK executable spec, relocation, debug info - Linking & ABI: .fd files, LVO tables, register calling conventions - Exec kernel: tasks, interrupts, memory, signals, semaphores - AmigaDOS: file I/O, FFS/OFS layout, CLI/Shell scripting - Graphics: planar bitmaps, Copper programming, HAM/EHB modes - Intuition: screens, windows, IDCMP, BOOPSI - Devices: trackdisk, SCSI, serial, timer, audio, keyboard - Libraries: utility, expansion, IFFParse, locale, ARexx - Networking: bsdsocket API, SANA-II, TCP/IP stack comparison - Toolchain: GCC, vasm/vlink, SAS/C, NDK, debugging - Reverse engineering: IDA/Ghidra setup, compiler fingerprints, case studies - CPU & MMU: 68040/060 emulation libs, PMMU, cache management - Driver development: SANA-II, Picasso96/RTG, AHI audio All files include breadcrumb navigation. No local paths or proprietary content.
This commit is contained in:
Ilia Sharin
parent
f07a368bf1
commit
21751c0025
172 changed files with 19701 additions and 0 deletions
12
02_boot_sequence/README.md
Normal file
12
02_boot_sequence/README.md
Normal file
|
|
@ -0,0 +1,12 @@
|
|||
[← Home](../README.md)
|
||||
|
||||
# Boot Sequence — Overview
|
||||
|
||||
## Section Index
|
||||
|
||||
| File | Description |
|
||||
|---|---|
|
||||
| [cold_boot.md](cold_boot.md) | Power-on to Kickstart: hardware init, ROM checksum |
|
||||
| [kickstart_init.md](kickstart_init.md) | ROM scan, resident modules, ExecBase creation |
|
||||
| [dos_boot.md](dos_boot.md) | BootStrap, eb_MountList, startup-sequence |
|
||||
| [early_startup.md](early_startup.md) | Early Startup Control (ESC menu), boot priority |
|
||||
101
02_boot_sequence/cold_boot.md
Normal file
101
02_boot_sequence/cold_boot.md
Normal file
|
|
@ -0,0 +1,101 @@
|
|||
[← Home](../README.md) · [Boot Sequence](README.md)
|
||||
|
||||
# Cold Boot — Power-On to Kickstart
|
||||
|
||||
## Overview
|
||||
|
||||
When the Amiga powers on or is reset (Ctrl-Amiga-Amiga), the 68000 CPU begins execution from the ROM. The boot process progresses from raw hardware init through to a fully running AmigaOS desktop in approximately 3–8 seconds.
|
||||
|
||||
---
|
||||
|
||||
## Hardware Initialisation (Pre-ROM)
|
||||
|
||||
### 1. CPU Reset Vector
|
||||
|
||||
The 68000 reads two longwords from address `$000000`:
|
||||
```
|
||||
$000000: Initial SSP (Supervisor Stack Pointer)
|
||||
$000004: Initial PC (Program Counter) → ROM entry point
|
||||
```
|
||||
|
||||
On Amiga, these locations map to Kickstart ROM at `$FC0000` (256 KB) or `$F80000` (512 KB). The ROM image contains:
|
||||
- Word 0–1: SSP value (typically `$000400`)
|
||||
- Word 2–3: PC value → ROM entry point
|
||||
|
||||
### 2. ROM Checksum
|
||||
|
||||
First code executed: compute checksum of entire ROM. If it fails → **red screen of death** (solid red background, no further boot).
|
||||
|
||||
```
|
||||
Checksum: simple 32-bit additive checksum of all ROM longwords.
|
||||
Result must equal $FFFFFFFF (complement to zero).
|
||||
The last longword of the ROM is the complement value.
|
||||
```
|
||||
|
||||
### 3. Chip Register Reset
|
||||
|
||||
```
|
||||
- Write $7FFF to INTENA ($DFF09A) — disable all interrupts
|
||||
- Write $7FFF to INTREQ ($DFF09C) — clear all pending interrupts
|
||||
- Write $7FFF to DMACON ($DFF096) — disable all DMA
|
||||
- CIA chips: reset timer, serial, port registers
|
||||
```
|
||||
|
||||
### 4. Memory Detection
|
||||
|
||||
The ROM probes for available memory:
|
||||
```
|
||||
1. Test Chip RAM at $000000 by writing test patterns
|
||||
2. Size Chip RAM: 256 KB, 512 KB, 1 MB, or 2 MB
|
||||
3. Probe for Fast RAM at $C00000 (Ranger), $200000 (Slow/Ranger)
|
||||
4. Probe for Zorro II auto-config space at $E80000
|
||||
5. Probe for 32-bit fast RAM at $07000000+ (Zorro III)
|
||||
```
|
||||
|
||||
### 5. Display Diagnostic Colours
|
||||
|
||||
During boot, the background colour indicates progress:
|
||||
|
||||
| Colour | Stage |
|
||||
|---|---|
|
||||
| Dark grey | ROM checksum passed |
|
||||
| Light grey | Chip RAM sized |
|
||||
| White | ExecBase initialised |
|
||||
| Green flash | DOS boot starting |
|
||||
| **Red** | ROM checksum fail |
|
||||
| **Yellow** | Chip RAM test fail |
|
||||
| **Blue** | Alert (Guru Meditation) |
|
||||
|
||||
---
|
||||
|
||||
## ROM Layout
|
||||
|
||||
### 256 KB ROM (Kickstart 1.x)
|
||||
|
||||
```
|
||||
$FC0000–$FFFFFF (256 KB)
|
||||
$FC0000: Reset vectors (SSP + PC)
|
||||
$FC0008: ROM header (version, checksum)
|
||||
...
|
||||
$FC0020: First resident module (exec.library)
|
||||
...
|
||||
$FFFFFC: Checksum complement word
|
||||
```
|
||||
|
||||
### 512 KB ROM (Kickstart 2.0+)
|
||||
|
||||
```
|
||||
$F80000–$FFFFFF (512 KB)
|
||||
$F80000: Reset vectors
|
||||
$F80008: ROM header
|
||||
...
|
||||
$F80020: exec.library resident tag
|
||||
...
|
||||
$FFFFFC: Checksum complement
|
||||
```
|
||||
|
||||
---
|
||||
|
||||
## References
|
||||
|
||||
- RKRM: *Hardware Reference Manual* — reset chapter
|
||||
121
02_boot_sequence/dos_boot.md
Normal file
121
02_boot_sequence/dos_boot.md
Normal file
|
|
@ -0,0 +1,121 @@
|
|||
[← Home](../README.md) · [Boot Sequence](README.md)
|
||||
|
||||
# DOS Boot — Bootstrap, Mount List, Startup-Sequence
|
||||
|
||||
## Overview
|
||||
|
||||
After the Kickstart ROM initialises the kernel and resident modules, `dos.library` takes over to mount filesystems and run the user's startup scripts.
|
||||
|
||||
---
|
||||
|
||||
## Boot Sequence Flow
|
||||
|
||||
```
|
||||
Kickstart ROM init complete
|
||||
↓
|
||||
dos.library creates initial CLI process
|
||||
↓
|
||||
BootStrap module (strap) reads boot block from boot device
|
||||
↓
|
||||
Boot block executed (OFS/FFS bootblock code)
|
||||
↓
|
||||
Mount configured devices from MountList (DEVS:DOSDrivers/)
|
||||
↓
|
||||
Execute S:Startup-Sequence
|
||||
↓
|
||||
Execute S:User-Startup
|
||||
↓
|
||||
LoadWB (start Workbench)
|
||||
```
|
||||
|
||||
---
|
||||
|
||||
## Boot Block Format
|
||||
|
||||
The first 2 sectors (1024 bytes) of a bootable disk:
|
||||
|
||||
```
|
||||
Offset Size Description
|
||||
$000 4 Boot block ID: "DOS\0" (OFS), "DOS\1" (FFS), etc.
|
||||
$004 4 Checksum (complement to zero)
|
||||
$008 4 Root block pointer (usually 880)
|
||||
$00C ... Boot code (up to 1012 bytes of 68000 code)
|
||||
```
|
||||
|
||||
### Boot Block Types
|
||||
|
||||
| ID | Hex | Type |
|
||||
|---|---|---|
|
||||
| `DOS\0` | `444F5300` | OFS (Old File System) |
|
||||
| `DOS\1` | `444F5301` | FFS (Fast File System) |
|
||||
| `DOS\2` | `444F5302` | OFS + International |
|
||||
| `DOS\3` | `444F5303` | FFS + International |
|
||||
| `DOS\4` | `444F5304` | OFS + Dir Cache |
|
||||
| `DOS\5` | `444F5305` | FFS + Dir Cache |
|
||||
| `DOS\6` | `444F5306` | OFS + Long Filenames (OS 3.2) |
|
||||
| `DOS\7` | `444F5307` | FFS + Long Filenames (OS 3.2) |
|
||||
|
||||
---
|
||||
|
||||
## Boot Priority
|
||||
|
||||
Devices are booted in priority order. Highest priority device boots first:
|
||||
|
||||
| Device | Default Priority | Description |
|
||||
|---|---|---|
|
||||
| DF0: | 5 | First floppy drive |
|
||||
| DH0: | 0 | First hard disk partition |
|
||||
| DH1: | −5 | Second partition |
|
||||
| DF1: | −10 | Second floppy |
|
||||
|
||||
Set in mountlist: `BootPri = 0` or via HDToolBox.
|
||||
|
||||
---
|
||||
|
||||
## Startup-Sequence
|
||||
|
||||
Standard `S:Startup-Sequence` for OS 3.1:
|
||||
|
||||
```
|
||||
C:SetPatch QUIET ; apply ROM patches
|
||||
C:AddBuffers DH0: 50 ; filesystem buffers
|
||||
C:Version >NIL:
|
||||
FailAt 21
|
||||
MakeDir RAM:T RAM:Clipboards RAM:ENV RAM:ENV/Sys
|
||||
Copy >NIL: ENVARC: RAM:ENV ALL NOREQ
|
||||
Assign >NIL: T: RAM:T
|
||||
Assign >NIL: CLIPS: RAM:Clipboards
|
||||
Assign >NIL: REXX: S:
|
||||
Assign >NIL: PRINTERS: DEVS:Printers
|
||||
Assign >NIL: KEYMAPS: DEVS:Keymaps
|
||||
Assign >NIL: LOCALE: SYS:Locale
|
||||
Assign >NIL: LIBS: SYS:Classes ADD
|
||||
Assign >NIL: HELP: LOCALE:Help DEFER
|
||||
|
||||
C:IPrefs
|
||||
|
||||
ConClip >NIL:
|
||||
; Launch Workbench:
|
||||
LoadWB
|
||||
EndCLI >NIL:
|
||||
```
|
||||
|
||||
---
|
||||
|
||||
## Early Startup Control (Boot Menu)
|
||||
|
||||
Hold **both mouse buttons** during boot to access the Early Startup Control menu:
|
||||
|
||||
| Option | Description |
|
||||
|---|---|
|
||||
| Boot With No Startup-Sequence | Skip S:Startup-Sequence |
|
||||
| Boot Standard | Normal boot |
|
||||
| Boot With: [device list] | Select boot device |
|
||||
| Display Mode: [NTSC/PAL] | Override display standard |
|
||||
|
||||
---
|
||||
|
||||
## References
|
||||
|
||||
- RKRM: Boot chapter
|
||||
- NDK39: `dos/dosextens.h` — BootStrap
|
||||
55
02_boot_sequence/early_startup.md
Normal file
55
02_boot_sequence/early_startup.md
Normal file
|
|
@ -0,0 +1,55 @@
|
|||
[← Home](../README.md) · [Boot Sequence](README.md)
|
||||
|
||||
# Early Startup Control — Boot Options
|
||||
|
||||
## Overview
|
||||
|
||||
The **Early Startup Control** (ESC) menu appears when both mouse buttons are held during power-on or reset. It provides boot device selection, display mode override, and emergency recovery options.
|
||||
|
||||
---
|
||||
|
||||
## Activation
|
||||
|
||||
- **Both mouse buttons held** before the boot screen hand animation completes
|
||||
- On A1200: hold both buttons during "floppy click" phase
|
||||
- Requires Kickstart 2.0+ (not available on 1.3)
|
||||
|
||||
---
|
||||
|
||||
## Menu Options (OS 3.1)
|
||||
|
||||
```
|
||||
┌──────────────────────────────────┐
|
||||
│ EARLY STARTUP CONTROL │
|
||||
│ │
|
||||
│ Boot With No Startup-Sequence │
|
||||
│ Boot Standard │
|
||||
│ │
|
||||
│ Boot Device: │
|
||||
│ DF0: (pri 5) │
|
||||
│ DH0: (pri 0) │
|
||||
│ │
|
||||
│ Display Mode: │
|
||||
│ ● PAL ○ NTSC │
|
||||
│ │
|
||||
│ [BOOT] │
|
||||
└──────────────────────────────────┘
|
||||
```
|
||||
|
||||
---
|
||||
|
||||
## Recovery Scenarios
|
||||
|
||||
| Scenario | Fix |
|
||||
|---|---|
|
||||
| Corrupted Startup-Sequence | Boot with No Startup-Sequence, then `ED S:Startup-Sequence` |
|
||||
| Wrong display mode (no image) | Hold both buttons → change PAL/NTSC |
|
||||
| Boot from floppy instead of HD | Select DF0: as boot device |
|
||||
| Assign loops / infinite boot | No Startup-Sequence → fix assigns manually |
|
||||
|
||||
---
|
||||
|
||||
## References
|
||||
|
||||
- RKRM: Early Startup chapter
|
||||
- OS 3.1 AmigaGuide: `System/BootMenu`
|
||||
104
02_boot_sequence/kickstart_init.md
Normal file
104
02_boot_sequence/kickstart_init.md
Normal file
|
|
@ -0,0 +1,104 @@
|
|||
[← Home](../README.md) · [Boot Sequence](README.md)
|
||||
|
||||
# Kickstart Initialisation — ROM Scan, ExecBase, Resident Modules
|
||||
|
||||
## Overview
|
||||
|
||||
After hardware init, the Kickstart ROM creates `ExecBase` and scans for **resident modules** — the OS components compiled into ROM. This process builds the entire OS kernel from tagged structures embedded in the ROM image.
|
||||
|
||||
---
|
||||
|
||||
## ExecBase Creation
|
||||
|
||||
1. Allocate ExecBase structure at a known address (end of Chip RAM)
|
||||
2. Initialise memory lists, library list, device list, resource list
|
||||
3. Store ExecBase pointer at **address `$000004`** — the global `SysBase`
|
||||
4. Initialise the Supervisor stack, interrupt vectors, trap vectors
|
||||
|
||||
```
|
||||
After this step:
|
||||
*(ULONG *)4 == ExecBase pointer
|
||||
SysBase->LibNode.lib_Version == Kickstart version
|
||||
```
|
||||
|
||||
---
|
||||
|
||||
## Resident Module Scan
|
||||
|
||||
The ROM scanner searches for **RomTag** markers (`$4AFC`) throughout the ROM address range:
|
||||
|
||||
```c
|
||||
struct Resident {
|
||||
UWORD rt_MatchWord; /* $4AFC — magic marker */
|
||||
struct Resident *rt_MatchTag; /* pointer to self (verification) */
|
||||
APTR rt_EndSkip; /* skip past this address */
|
||||
UBYTE rt_Flags; /* RTF_COLDSTART, RTF_SINGLETASK, etc. */
|
||||
UBYTE rt_Version; /* version number */
|
||||
UBYTE rt_Type; /* NT_LIBRARY, NT_DEVICE, NT_RESOURCE */
|
||||
BYTE rt_Pri; /* init priority (higher = earlier) */
|
||||
char *rt_Name; /* module name */
|
||||
char *rt_IdString; /* version string */
|
||||
APTR rt_Init; /* init function or auto-init table */
|
||||
};
|
||||
```
|
||||
|
||||
### Scan Algorithm
|
||||
|
||||
```
|
||||
for addr in ROM_START to ROM_END step 2:
|
||||
if *(UWORD *)addr == $4AFC:
|
||||
tag = (struct Resident *)addr
|
||||
if tag->rt_MatchTag == tag: /* self-pointer validates */
|
||||
add to resident list
|
||||
addr = tag->rt_EndSkip /* skip past module */
|
||||
```
|
||||
|
||||
---
|
||||
|
||||
## Initialisation Phases
|
||||
|
||||
Residents are initialised in **priority order** within each phase:
|
||||
|
||||
### Phase 1: RTF_COLDSTART (flags bit 0)
|
||||
|
||||
Called during cold boot, single-tasking (no scheduler yet):
|
||||
|
||||
| Priority | Module | Description |
|
||||
|---|---|---|
|
||||
| 126 | `exec.library` | Core kernel |
|
||||
| 120 | `expansion.library` | AutoConfig Zorro boards |
|
||||
| 105 | `68040.library` | CPU trap handlers (if present) |
|
||||
| 100 | `utility.library` | Tag/hook support |
|
||||
| 70 | `graphics.library` | Display init |
|
||||
| 50 | `layers.library` | Clipping layers |
|
||||
| 50 | `intuition.library` | GUI subsystem |
|
||||
| 40 | `timer.device` | Timing services |
|
||||
| 30 | `keyboard.device` | Keyboard |
|
||||
| 20 | `input.device` | Input event merging |
|
||||
| 10 | `trackdisk.device` | Floppy |
|
||||
| −50 | `dos.library` | AmigaDOS file system |
|
||||
| −120 | `ramlib` | Disk-based library/device loader |
|
||||
|
||||
### Phase 2: RTF_SINGLETASK
|
||||
|
||||
Runs after all COLDSTART modules but before multitasking begins. Used by strap (bootstrap) module.
|
||||
|
||||
### Phase 3: RTF_AFTERDOS
|
||||
|
||||
Runs after DOS is available. External disk-based modules.
|
||||
|
||||
---
|
||||
|
||||
## After Resident Init
|
||||
|
||||
1. Multitasking enabled (scheduler starts)
|
||||
2. `dos.library` creates initial CLI process
|
||||
3. Boot task launches `strap` → reads boot block from DF0: or boot device
|
||||
4. Control passes to `startup-sequence`
|
||||
|
||||
---
|
||||
|
||||
## References
|
||||
|
||||
- NDK39: `exec/resident.h`
|
||||
- RKRM: Resident modules chapter
|
||||
Loading…
Add table
Add a link
Reference in a new issue