An explanation of MSCDEX naming syntax in MS-DOS

First, the MSCDEX syntax and parameters:
The MSCDEX can be loaded automatically in the Autoexec.bat file, or it can be loaded on a DOS command line but with an optical drive, provided the driver for the optical drive is loaded into the Config.sys file. The syntax format for MSCDEX is:
C:\DOS\MSCDEX. Exe/d:driver1 [/d:driver2][/e][/k][/s][/v][/l:letter][/m:number]
The meanings of the parameters are as follows:
/d:driver1 [/d:driver2]
Use this parameter to specify the machine symbol for the CD-ROM drive. If you have more than one CD-ROM drive in your computer, MSCDEX allows you to specify machine symbols for several CD-ROM drives at the same time. For example, if more than two CD-ROM drives are installed on the computer, then the machine symbol for the first drive is specified as MSCD000 (DRIVER1) or other symbols, then the machine symbol for the subsequent drive is MSCD001 (DRIVER2). It should be noted that the machine symbol for the CD-ROM drive specified here must be the same as the machine symbol for the CD-ROM drive specified in the Config.sys file loading CD-ROM device driver command line (pairing appears).
This means that at least one/d:driver parameter must be included in the MSCDEX command line. If you have more than one CD-ROM device drive installed on your computer, you should specify the appropriate/d:driver parameter for each CD-ROM device drive and ensure that it is the same as the symbol specified in the corresponding command line for the Config.sys file.
/E
If possible, specify that the CD-ROM uses the computer's expanded memory as the buffer sector for its data transfer.
/k
Enables MS-DOS to recognize the Kanji encoded volume label name of the CD-ROM. By default, this volume label name is not recognized by MS-DOS. (Kanji encoding is one of the encodings in Japanese)
/S
Implement CD-ROM sharing in a network working environment such as ms-net or Windows for Workgroups.
/V
Displays statistics of computer memory usage during MSCDEX startup.
/l:letter
Specifies the drive letter assigned to the first CD-ROM drive. If more than one CD-ROM drive is installed on the computer, MS-DOS assigns the following available drive letters to the other drives in turn. However, this parameter is limited by the lastdrive command in the Config.sys file.
/m:number
Specifies the number of buffer sectors assigned to the CD-ROM drive.
Note: There is a point in writing in the command line where there should be a space between the parameter and the command-line arguments and arguments, otherwise, MSCDEX will not recognize this parameter during execution and an error message appears:
Illegal FUNCTION. (Illegal function)
Second, MSCDEX use example:
1. Install a single CD-ROM device drive:
In the example, only the command line associated with a single CD-ROM device drive in the Config.sys and Autoexec.bat files is listed.
For example, the following command line to mount the CD-ROM driver is included in the Config.sys file:
Device=c:\devices\cdromdrv. sys/dmscd000
The following command line should be included in the Autoexec.bat file:
C:\DOS\MSCDEX. exe/d:mscd000/e/l:g
These two commands exercise the CD-ROM drive as a usable device for MS-DOS and specify that its machine symbol is MSCD000. Where the/e parameter specifies that the drive will use expanded memory as its buffer sector under possible conditions, while the/L:G parameter specifies that the letter G be assigned to the CD-ROM drive.
2. Install multiple CD-ROM device drives:
In the example, the command lines associated with the two CD-ROM drives in the Config.sys and Autoexec.bat files are listed. These two CD-ROM drives are produced by different manufacturers.
For example, in the Config.sys file, the following two command lines are included to mount the CD-ROM device driver:
Device=c:\aspi\aspicd. sys/d:mscd000
Device=c:\cdrom\tslcdr. sys/d:mscd001
The following command line should be included in the Autoexec.bat file:
C:\DOS\MSCDEX. Exe/d:mscd000/d:mscd001/l:g
The above command to exercise MS-DOS can use two CD-ROM drives simultaneously. The machine symbol for the first drive is specified as MSCD000, and the machine symbol for the second drive is specified as MSCD001. The parameter/l:g specifies that the machine symbol assigned to the first is specified as MSCD001. Parameter/l:g specifies that the drive letter assigned to the first CD-ROM drive (MSCD000) is G and the drive letter of the second drive (MSCD001) is assigned to h in turn.
As can be seen from the example above, the specified machine symbol for the same CD-ROM drive in the Config.sys and Autoexec.bat files is paired.
Three, mscdex of several notes:
1. The device driver for the CD-ROM drive must be mounted in the Config.sys file with either device or Devicehigh command before using MSCDEX, or the following error message will appear when you run MSCDEX:
DEVICE DRIVER not FOUND: ' MSCD000 '
NO VALID CDROM DEVICE DRIVERS SELECTED.
MSCD000 device driver not found, no valid CD-ROM drive)
The command line that equips the device driver must contain at least one/d:driver parameter. This parameter is assigned to the CD-ROM drive as a machine symbol for internal computer recognition.
The command line that uses MSCDEX in the Autoexec.bat file must also contain at least one/d:driver parameter, paired with the machine symbol specified in the Config.sys file. MSCDEX Use this parameter to identify the correct CD-ROM device. This parameter specifies that the drive's machine symbol is usually similar to MSCD000 in this form. Each available CD-ROM device drive must have a unique drive name (machine symbol).
2. The number of logical drives determined by the lastdrive command in Config.sys affects the number of CD-ROM drives in the computer. Some of the available drive letters may be used by other programs, such as a network drive or a DoubleSpace host disk. At this point, the number of logical drives by the lastdrive command should be as large as possible. Of course, depending on the circumstances, such as: a common home computer, hard disk partition C and D zone, and uncompressed, with a CD-ROM drive, then lastdrive=f can also, more settings is unnecessary waste.
3. If SMARTDRV is used in the computer, make sure that the command line martdrv can speed up the data transfer of the CD-ROM drive before the SMARTDRV command line is MSCDEX in the Autoexec.bat file. Sometimes there may be some conflicts, especially when playing a VCD, you can use the SMARTDRV/u parameter to disable buffering of the CD-ROM to solve the problem.
The 4.cd-rom device driver is correctly installed with the following flags: The drive letter is correctly recognized at the DOS prompt and in other applications. Otherwise, you should carefully check whether the relevant driver in the Config.sys file is installed, or check that the MSCDEX command line in the Autoexec.bat file is in the correct format.

An explanation of MSCDEX naming syntax in MS-DOS