Overview of Architecture and Application of Clone OS

Overview of Architecture and Application of Clone OS

Divyavrat Jugtawat divyavrat@live.com JIET, Jodhpur, India

Abstract

Clone OS was made to be a portable OS. It can run from any drive with portable usage. Clone OS en-capsules many new ideas we had for a controlled OS. We are going to explain these new features along with the new freedom it provides to its users. Books can be read on the move, on any computer using this OS. Also ASCII art was never truly supported by other OS before. Clone OS has inbuilt ASCII editors with complete saving and creating frames with each ASCII page. Clone OS also has binary code environment to allow machine coders to code there programs directly with them being saved as a file. This can be used instead of the costly machine kits or simulators. Clone OS also has DOS compatibility, i.e. COM programs of DOS can be run in Clone OS and vice-versa. This extends to all OS that have a DOS API, including Windows till Xp, React OS and CP/M OS. Clone OS allows more and more support for existing materials and so all existing e-book formats like TXT, DOC are supported and others can be converted to these formats. Following is the Description of a new Operating System and the new methods used by it. Its new shell interface and commands. Its API and interrupts are explained.

Keywords

Clone, OS, API, portable OS, USB, command, single-tasking, ASCII art.

Introduction

There was always a need to create a portable working environment. Most linux distributions allow this but files that are made are not saved once the live CD/USB is removed. Hence we started creating a bootable USB with small OS that can perform basic file management and compatibility with existing OS. Hence Clone OS has ported basic file formats like TXT to work with. Clone OS has hence inherited the basic DOS formats of COM for programs and BMP for images. This is a description of a new Operating System. Some completely new ideas are presented in the OS that needed to be described. Clone OS has a different approach to the common tasks like file management and shell interface. These new ideas are presented here.

Clone OS is a real-mode OS that commonly

works in 16-bit with occasional 32-bit usage. It can be extended to long-mode or protected mode.

How Clone OS is loaded

The first sector of the drive is the bootloader with the last two bytes set as the magic numbers 0x55AA. This tells the BIOS to load it at 0x7C00 location and run it. This bootloader parses the FAT12 root directory located at LBA

0x0013 and finds the OS or asks you to choose one. This entry in root directory tells the first cluster of the file and this can be read until the cluster with value > 0xFF0 is reached. This OS is then run with drive number given in dl register.

Initialization

Now since the stack could be set anywhere, they need to be initialized.

Clone OS sets stack segment ss to 0x9000 and stack pointer sp to 0xFFFF, so we have a large space for stack usage.

After this ds is set to zero as well as es, fs, gs

are initialized to zero.

Now we can save the dl value given by the bootloader to the drive (system variable).

After the save, we switch to protected mode and back to real mode to get in unreal mode to have both larger memory and BIOS interrupts. All main memory is thus assessable.

In unreal mode, now we set up the IVT with the custom Interrupt handlers for the OS API in int 0x21,0x61,0x64, etc and for exceptions int 0x01,0x03,0x05,0x06, etc.

After interrupts are set up, a custom user selected autorun string is run.

The autorun commonly contains commands to run –

CONFG (configuration and settings program)

PWD(Password Utility) and

vlh (mints to show version and help).

Shell

Clone OS has a command line interface. Its shell is tightly combined and mixed in kernel.

Shell starts by showing prompt and receiving a string that can end with enter or space.

These commands are then compared with the list of available commands and if not found, a small error is shown. Shell can be used by programs to run preexisting commands. Clone OS has a flexible approach to all user interface. Thus all Shell colors are customizable. The Default prompt can be changed and custom fonts can be setup to allow all personalization. Shell can be used by programs in the API to use

shell commands.

Why Clone OS was built

It was made and chosen to be a small, portable OS that can run anywhere and used to do everyday jobs with a controlled flow of flexibility and user control over the complete OS. Clone OS was made to be extremely small and run completely from RAM i.e. its a completely live OS. It can be run from a –

Hard disk (HDD) Pen drive (USB) Memory card (SD) Floppy disk (FDD)

or any other method that emulates the HDD CHS with 512b sectors.

Books can be read on the move, on any computer using this OS. Also ASCII art was never truly supported by other OS before.

Clone OS has inbuilt ASCII editors with complete saving and creating frames with each ASCII page.

Clone OS also has binary code environment to allow machine coders to code there programs directly with them being saved as a file. This can be used instead of the costly machine kits or simulators.

Clone OS also has DOS compatibility, i.e. COM programs of DOS can be run in Clone OS and vice-versa. This extends to all OS that have a DOS API, including Windows till Xp, React OS and CP/M OS. Clone OS allows more and more support for existing materials and so all existing ebook formats like TXT, DOC are supported and others can be converted to these formats.

Mints

One of the unique new abilities of Clone OS is Mints.

Mints are characters that can be combined in any manner to make custom commands. Each character in the mint collection is a command. There is no restriction to the length of commands that can be made.

Common mints are – t – time, d-date, p-pause,

etc.

Thus if we write – tptdclvllph

it will show time, pause, time, clock, line, show version, line, pause, and finally show help.

The OS has the API setup to allow programmers to use the mints in their own programs.

Directories, programs and files

All above are treated as file locations. They can be assessed by their file names or their LBA address or CHS sectors. Also each directory is given a unique hexadecimal code, so the common tree structure of assessing files can be skipped and can be jumped to the needed folder immediately.

ASCII art

All 256 characters and 16×16 colors can be used to create any possible painting. Large support exists online for ASCII art by notepad but that allowed only one color and one font.

This ASCII format allows large graffiti to made in small size. E-books can be made with this structure. Also Frames can be combined to make videos. Cards API is provided to allow ASCII art for games.

Applications

Most common programs are made in COM format. Clock, password system, saved settings, games like ping-pong and snake. Educational simulators like that of stack. And utilities like

Screen-savers and portable text and code editors. All Dwarf OS applications can be run directly on Clone OS too. Basic applications like Hex editor, EBook Reader and ASCII editors are inbuilt in this OS. More applications can be simply copied to the drive to add them to the OS.

Microkernel

Clone OS is also a monolithic kernel with a microkernel. Thus common programs are included in te OS but can be extended to more programs by simply copying the program in the drive. Common utilities are added as files.

Common Keys – Esc, ~ to Close F1 for help

Tab to change video page F10 to quit

Also Ctrl+brk is set up to interrupt any running code to show debug values and pause.

During this pause press F10 to return to shell. This method can be used to close a program forcibly.

This method works like (Ctrl+Alt+Del).

System data –

CHS method – head, track LBA method – H T S cluster

size – number of sectors to load(used by both CHS and LBA)

color1 – this color is used by the custom text type mode.

color2 -this is used by the BIOS teletype method.

drive – to be used by common loading and saving commands as the drive number

(0x00 = floppy, 0x80 = HDD )

drive2 -install command uses this to copy files from drive1 to drive2.

prompt – default command string.

API

All of the common tasks faced by the programmer are provided in the API as int 0x21, 0x61, 0x64.

Common API tasks are provided like – Strings –

display string, get string, read char, show char

Keys-

getch, getch without echo, direct key input

File Management –

open file, open directory, new file, save file, read LBA, and a file selector is provided.

Process Management –

other processes can be run, and closed by different ways. User commands can be piped to allow instruction processing with different modules.

Debugging options are provided to you in int 0x60 or opcode 0xCC can be used for a breakpoint.

TUI components like –

Message Box, Input Box, save screen and restore are provided.

And all other everyday components required by programmers like –

clrscr, newline, position setup, and getting integers or bigger numbers is already set to be quickly used by the developers.

Problems faced –

No good e-book format was found to provide a good reading experience in smaller sizes.

Pictures have to be set in books but this made

large sized books and lesser creative control. This was solved by creating a new book type

.PIC which can contain both text and pictures in very small space. It also allows variable experimentation features to be used.

Also too less .COM programs had existed, so our developers sat straight to remake the basic utilities.

Future Work –

FAT16 is planned to be added as another driver. Mouse support can be added to int 0x33 .

GUI mode can be made additional to current CLI.

EXE files can be run.

Additional compilers for higher level languages.

Other architectures like SPARC and ARM can be supported.

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