DOSEmu Technical Guide

The DOSEmu team, Edited by Alistair MacDonald <alistair@slitesys.demon.co.uk>

1. Introduction

2. Runtime Configuration Options

• 2.1 Format of /etc/dosemu.users
• 2.2 Format of /var/lib/dosemu/global.conf ( (old) .dosrc, -I option)

3. Accessing ports with dosemu

• 3.1 General
• 3.2 Port I/O access

4. The Virtual Flags

5. VM86PLUS, new kernel's vm86 for a full feature dosemu

• 5.1 Restrictions
• 5.2 Parts in the kernel that get changed for vm86plus
• 5.3 Abandoned `bells and whistles' from older emumodule

6. Video Code

• 6.1 C files
• 6.2 Header files
• 6.3 Notes
• 6.4 Todo

7. The old way of generating a bootable DOSEmu

• 7.1 Boot ( tool generated `hdimage' method )
• 7.2 Boot ( `traditional' method )

8. New Keyboard Code

• 8.1 Whats New
• 8.2 Status
• 8.3 Keyboard server interface
• 8.4 Keyboard server structure
• 8.5 Known bugs & incompatibilites
• 8.6 Changes from 0.61.10
• 8.7 TODO

9. IBM Character Set

• 9.1 What's new in configuration
• 9.2 THE FUTURE by Mark Rejhon

10. Setting HogThreshold

11. Priveleges and Running as User

• 11.1 What we were suffering from
• 11.2 The new 'priv stuff'

12. Timing issues in dosemu

• 12.1 The 64-bit timers
• 12.2 DOS 'view of time' and time stretching
• 12.3 Non-periodic timer modes in PIT
• 12.4 Fast timing
• 12.5 PIC/PIT synchronization and interrupt delay
• 12.6 The RTC emulation
• 12.7 General warnings

13. Pentium-specific issues in dosemu

• 13.1 The pentium cycle counter
• 13.2 How to compile for pentium
• 13.3 Runtime calibration
• 13.4 Timer precision
• 13.5 Additional points

14. The DANG system

• 14.1 Description
• 14.2 Changes from last compiler release
• 14.3 Using DANG in your code
• 14.4 DANG Markers
• 14.5 DANG_BEGIN_MODULE / DANG_END_MODULE
• 14.6 Usage
• 14.7 Future

15. mkfatimage -- Make a FAT hdimage pre-loaded with files

16. mkfatimage16 -- Make a large FAT hdimage pre-loaded with files

17. Documenting DOSEmu

• 17.1 Sections
• 17.2 Emphasising text
• 17.3 Lists
• 17.4 Quoting stuff
• 17.5 Special Characters
• 17.6 Cross-References & URLs
• 17.7 Gotchas

18. Sound Code

• 18.1 Current DOSEmu sound code
• 18.2 Original DOSEMU sound code

19. DMA Code

• 19.1 Current DOSEmu DMA code
• 19.2 Original DOSEMU DMA code

20. DOSEmu Programmable Interrupt Controller

• 20.1 Other features
• 20.2 Caveats
• 20.3 Notes on theory of operation:
• 20.4 A (very) little technical information for the curious

21. DOSEMU debugger v0.6

• 21.1 Introduction
• 21.2 Usage
• 21.3 Commands
• 21.4 Performance
• 21.5 Wish List
• 21.6 BUGS

22. MARK REJHON'S 16550 UART EMULATOR

• 22.1 PROGRAMMING INFORMATION
• 22.2 DEBUGGING HELP
• 22.3 FOSSIL EMULATION
• 22.4 COPYRIGHTS

23. Recovering the console after a crash

• 23.1 The mail message

24. Net code