Characteristics and Differences of Various Versions of MS-DOS
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The Digital Research company once monopolized the 8-bit microcomputer market with its developed CP/M-80 operating system. But the early versions DOS 1.00 and DOS 1.10 selected by IBM were improved by Microsoft Corporation from the purchased 8-bit CP/M operating system, and thus the company currently holds most of the market for 16-bit microcomputer operating systems. Nowadays, the MS-DOS operating system has become a naturally formed customary standard and is also a general operating system for low-end 16-bit microcomputer users. Therefore, this article introduces the characteristics and main differences of various DOS versions, so as to help readers select a suitable DOS version according to the grade of their machine models and avoid blindly pursuing high versions on low-end machines.
DOS 1.00 and DOS 1.10 are extended versions of the 8086/8088 CP/M operating system, which is an improvement of the 8-bit microcomputer to 16-bit microcomputer CP/M operating system. Its functions are simple, it does not support hard disks, and there are not many application programs provided.
DOS 2.00 version has a great expansion in structure compared with DOS 1.10 version. The main added part is providing part of the use interface of UNIX. The major improvement in its structure is: supporting one or more fixed disks. Fixed disks can be partitioned, and each partition can use different operating systems. Starting from DOS 2.00, DOS formats software with nine sectors per track. The disk buffer is a piece of user memory area reserved when DOS is started. When performing disk operations, DOS 2.00 allows you to choose the number of buffers reserved when starting the system from 1 to 99. If there is a large amount of memory, setting multiple buffers will make your program run faster. It supports a tree-structured directory. This new feature allows you to place all related groups of files on the same disk under their own directories, and the directories are isolated from each other. When viewing directories from the root directory in logical order, the directory structure is as clear as a tree structure. Disk volume labels are added. Extended screen and keyboard control functions can send special string controls to the screen color and cursor position in the program. It also allows you to redefine the meaning of any key on the keyboard. The pipeline function of standard input and output is added. The special character "" (output) can make the program receive external input from non-keyboard or specify output to non-screen destination devices. The water flow operation of standard input and output is added, making DOS like a "pipeline" where the output of the first program points to the input of the second program. The special characters "" and "\" have new meanings for DOS and can no longer be used in file names. Some commands are added, such as ASSING, BACKUP, BREAK, CLS, CTTY, ECHO, IF, FOR, SHIFT, GOTO, FDISK, GRAPHICS, MKDIR, RMDIR, CHDIR, PATH, PRINT, PROMPT, REC, VER, RESTORE, SET, TREE, VER, VERIFY, VOL, etc.
On the DOS 2.00 version, modifications were made to the system interior to be suitable for the characteristics of the half-high floppy disk drives of PC/TR and PC PORtable (portable) machines, and no new commands were added, still occupying 24KB of memory.
The DOS 3.00 version was launched in 1984 for the PC/AT machine. It can support the 1.2MB high-density floppy disk drive and 20MB large-capacity hard disk configured by the IBM PC/AT machine. It also provides a virtual disk (Virtual disk), which is a disk simulated by using memory. The system occupies 36KB. The external command can be prefixed with a string to describe the subdirectory where the command is located, and a major change is made in the internal command file allocation table (FAT). Each item of the file allocation table is represented by a 16-bit binary number instead of a 12-bit binary number. Therefore, a disk can have a maximum of 65536 clusters instead of the original 4096 clusters, and the size of the cluster means that in a disk of the same size, each cluster can have a smaller space, so the disk space usage will be more efficient. File sharing functions required by multi-user systems and network users are also added. System function calls are increased to strengthen file management capabilities. It supports Basic 3.0 version, allowing users to install device drivers based on Basic and execute DOS commands by themselves.
The DOS 3.10 version still occupies 36KB of memory space. It mainly adds network functions and provides SUBST and JOIN commands. If the network function is not used, the DOS 3.10 version is almost exactly the same as the DOS 3.00 version.
The DOS 3.2 version is launched for the portable PC machine. It mainly adds the function of the 3.5-inch 720KB floppy disk drive, and also adds commands such as REPLACE, XCOPY, and token network functions and I/O control.
The characteristics of the DOS 3.30 version are adding some new device drivers and some external commands, such as DISPLAY.SYS, APPEND, etc., adding the concept of code pages. It can be used not only for PC/XT, AT Great Wall series machines but also for IBM PS/2 machines.
The DOS 4.0 version was launched in June 1988, and the subsequent 4.01 version can support all the IBM PS/2 family.
The characteristics of the DOS 4.×× version are: supporting large hard disk partitions. Before DOS 3.3, the maximum capacity of the basic DOS partition was limited to within 33MB, while for the DOS 4.×× version, the basic DOS partition can be larger than 33MB, and the buffer is increased from 99 to 10000, which can greatly improve the DOS disk performance and speed up program operation. The expanded FASTOPEN function can greatly improve the random access performance of large disk files.
From the above, it can be seen that except that DOS 3.10 is for the need of adding network functions, the changes of other versions are mainly launched for the upgrade of disk drives.
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The Digital Research company once monopolized the 8-bit microcomputer market with its developed CP/M-80 operating system. But the early versions DOS 1.00 and DOS 1.10 selected by IBM were improved by Microsoft Corporation from the purchased 8-bit CP/M operating system, and thus the company currently holds most of the market for 16-bit microcomputer operating systems. Nowadays, the MS-DOS operating system has become a naturally formed customary standard and is also a general operating system for low-end 16-bit microcomputer users. Therefore, this article introduces the characteristics and main differences of various DOS versions, so as to help readers select a suitable DOS version according to the grade of their machine models and avoid blindly pursuing high versions on low-end machines.
DOS 1.00 and DOS 1.10 are extended versions of the 8086/8088 CP/M operating system, which is an improvement of the 8-bit microcomputer to 16-bit microcomputer CP/M operating system. Its functions are simple, it does not support hard disks, and there are not many application programs provided.
DOS 2.00 version has a great expansion in structure compared with DOS 1.10 version. The main added part is providing part of the use interface of UNIX. The major improvement in its structure is: supporting one or more fixed disks. Fixed disks can be partitioned, and each partition can use different operating systems. Starting from DOS 2.00, DOS formats software with nine sectors per track. The disk buffer is a piece of user memory area reserved when DOS is started. When performing disk operations, DOS 2.00 allows you to choose the number of buffers reserved when starting the system from 1 to 99. If there is a large amount of memory, setting multiple buffers will make your program run faster. It supports a tree-structured directory. This new feature allows you to place all related groups of files on the same disk under their own directories, and the directories are isolated from each other. When viewing directories from the root directory in logical order, the directory structure is as clear as a tree structure. Disk volume labels are added. Extended screen and keyboard control functions can send special string controls to the screen color and cursor position in the program. It also allows you to redefine the meaning of any key on the keyboard. The pipeline function of standard input and output is added. The special character "" (output) can make the program receive external input from non-keyboard or specify output to non-screen destination devices. The water flow operation of standard input and output is added, making DOS like a "pipeline" where the output of the first program points to the input of the second program. The special characters "" and "\" have new meanings for DOS and can no longer be used in file names. Some commands are added, such as ASSING, BACKUP, BREAK, CLS, CTTY, ECHO, IF, FOR, SHIFT, GOTO, FDISK, GRAPHICS, MKDIR, RMDIR, CHDIR, PATH, PRINT, PROMPT, REC, VER, RESTORE, SET, TREE, VER, VERIFY, VOL, etc.
On the DOS 2.00 version, modifications were made to the system interior to be suitable for the characteristics of the half-high floppy disk drives of PC/TR and PC PORtable (portable) machines, and no new commands were added, still occupying 24KB of memory.
The DOS 3.00 version was launched in 1984 for the PC/AT machine. It can support the 1.2MB high-density floppy disk drive and 20MB large-capacity hard disk configured by the IBM PC/AT machine. It also provides a virtual disk (Virtual disk), which is a disk simulated by using memory. The system occupies 36KB. The external command can be prefixed with a string to describe the subdirectory where the command is located, and a major change is made in the internal command file allocation table (FAT). Each item of the file allocation table is represented by a 16-bit binary number instead of a 12-bit binary number. Therefore, a disk can have a maximum of 65536 clusters instead of the original 4096 clusters, and the size of the cluster means that in a disk of the same size, each cluster can have a smaller space, so the disk space usage will be more efficient. File sharing functions required by multi-user systems and network users are also added. System function calls are increased to strengthen file management capabilities. It supports Basic 3.0 version, allowing users to install device drivers based on Basic and execute DOS commands by themselves.
The DOS 3.10 version still occupies 36KB of memory space. It mainly adds network functions and provides SUBST and JOIN commands. If the network function is not used, the DOS 3.10 version is almost exactly the same as the DOS 3.00 version.
The DOS 3.2 version is launched for the portable PC machine. It mainly adds the function of the 3.5-inch 720KB floppy disk drive, and also adds commands such as REPLACE, XCOPY, and token network functions and I/O control.
The characteristics of the DOS 3.30 version are adding some new device drivers and some external commands, such as DISPLAY.SYS, APPEND, etc., adding the concept of code pages. It can be used not only for PC/XT, AT Great Wall series machines but also for IBM PS/2 machines.
The DOS 4.0 version was launched in June 1988, and the subsequent 4.01 version can support all the IBM PS/2 family.
The characteristics of the DOS 4.×× version are: supporting large hard disk partitions. Before DOS 3.3, the maximum capacity of the basic DOS partition was limited to within 33MB, while for the DOS 4.×× version, the basic DOS partition can be larger than 33MB, and the buffer is increased from 99 to 10000, which can greatly improve the DOS disk performance and speed up program operation. The expanded FASTOPEN function can greatly improve the random access performance of large disk files.
From the above, it can be seen that except that DOS 3.10 is for the need of adding network functions, the changes of other versions are mainly launched for the upgrade of disk drives.
ko20010214
=================================
大功告成，打个Kiss!
ko20010214@MSN.com
神州优雅Q300C
Intel CeleronM 370处理器 | 256MbDDR内存
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=================================
大功告成，打个Kiss!
ko20010214@MSN.com
神州优雅Q300C
Intel CeleronM 370处理器 | 256MbDDR内存
40G硬盘 | USB2.0 | IEEE 1394
13.3 ' WXGA 宽屏(16:10) | COMBO光驱
10/100M网卡 | 四合一读卡器
