Interrupt INT 21h:
1, Character-Oriented Function)
01H, 07H and 08H - input from standard input equipment
02H - Character output
03H - Enter the auxiliary equipment
04H - Output of auxiliary equipment
05H - print output
06H - Console Input / Output
09h - Display string
0AH - Keyboard buffer input
0BH - detect input state
0ch - Enter the input function of the input buffer
(1), function 01h, 07h and 08h
Function Description: Reads a character from a standard input device (such as a keyboard). This interrupt will always be in the waiting state until a character readable during processing. This input can also be redirected. If this is done, it is impossible to determine if the file has arrived at the end of the file.
Entrance parameters: AH = 01H, filter out the control character, and display
= 07h, but filter out the control character, not exposed
= 08h, filter out the control character, no return
Export Parameters: Al = ASCII code for input characters
(2), function 02h
Function Description: Output a character to the standard output device (e.g., screen). This output can also be redirected. If this is done, it will not be able to judge whether the disk is full.
Entrance parameters: ah = 02h
DL = ASCII code to be output
Export parameters: no
(3), function 03h
Function Description: Read a character from the auxiliary device, the default value of the auxiliary device is COM1
Entrance parameters: AH = 03H
Export Parameters: Al = ASCII code read into characters
(4) Function 04h
Function Description: Output a character to the auxiliary device, the default value of the auxiliary device is COM1
Entrance parameters: ah = 04h
DL = ASCII code to be output
Export parameters: no
(5), function 05h
Function Description: Output a character to the standard output device. The default output device is the printer of the LPT1 port unless changed with the MODE command.
Entrance parameters: AH = 05H
DL = ASCII code to be output
Export parameters: no
(6), function 06h
Function Description: Console (such as: Keyboard, Screen) Input / Output. If the input / output operation is redirected, then the file will not be determined whether the file has arrived, or the disk is full.
Entrance parameters: AH = 06h, DL = input / output function selection
Export Parameters: If DL = 00h-Feh, this function is output, DL is the ASCII code to be output;
If DL = 0ffh, this function is input. At this time: If ZF = 1, there is no character readable, otherwise, Al = ASCII code read into characters
(7), function 09h
Function Description: Outputs a string to the standard output device. If the output is redirected, then the disk will not be judged.
Entrance parameters: AH = 09h
DS: DX = address to be output
Description: The string to be displayed is ended as '$'.
Export parameters: no
(8), function 0AH
Function Description: Read a byte string from a standard input device, encountering the "Enter key" end input (the input character is returned on the standard output device). If the input operation is redirected, then it will not be able to determine if the file has arrived at the end of the file.
Entrance parameters: AH = 0ah
DS: DX = Start address of the input character accepts the definition of the input string buffer:
1. The first byte is the maximum capacity of the buffer, which is considered to be an entry parameter;
2, the second byte is the number of characters (excluding the Enter key), which can be seen as an export parameter;
3. Start the actual input string from the third byte;
4, the string ends with the Enter key, and the carriage return is the last character accepted;
5. If the number of characters entered exceeds the maximum capacity of the buffer, the multi-out portion is discarded, the system and the ringing until the "Enter" key is entered.
E.g:
BUFF 80, 80 DUP (?); Up to 80 characters
Export parameters: no
(9), function 0BH
Function Description: Check if there is a character readable on the standard input device. This input operation can be redirected
Entrance parameters: ah = 0bh
Export Parameters: Al = 00H-- No Character Readable; FFH - Have Character Read
(10), function 0ch
Function Description: Empty the current standard input buffer and read the character. Its input operation can be redirected
Entrance parameters: ah = 0ch
Al = 01H, 06H, 07H, 08H or 0AH
Export Parameters: If the entrance parameter Al is 0ah, DS: DX = Start the start address of the input character, otherwise, the exit parameter AL = input character ASCII code
2, directory control function (Directory-Control function)
39h - Create a directory
3AH - Delete Directory
3bh - Set the current directory
47h - Read the current directory
(1), function 39h
Function Description: Create a new directory with the specified drive and path
Entrance parameters: AH = 39h
DS: DX = Specify the string address of the path (end sign with 0 is a string)
Export Parameters: CF = 0 - Create success, otherwise, AX = error number (03H or 05H), its meaning see error code table
(2), function 3AH
Function Description: Delete the directory of the specified drive and path
Entrance parameters: ah = 3ah
DS: DX = Specify the string address of the path (end sign with 0 is a string)
Export parameters: cf = 0 - Delete success, otherwise, ax = error number (03H or 05H), its meaning see the error code table
(3), function 3BH
Function Description: Set to the current directory with the specified drive and path
Entrance parameters: AH = 3BH
DS: DX = Specify the string address of the path (end sign with 0 is a string)
Export Parameters: CF = 0-- Set success, otherwise, AX = error number (03H), its meaning see the error code table
(4) Function 47h
Function Description: Take the full path string of the current directory
Entrance parameters: AH = 47h
DL = drive letter (0 = default, 1 = A, ...)
DS: Si = Address of the current directory string
Export parameters: cf = 0-- Read success, otherwise, ax = error number (0FH), its meaning see the error code table
3, disk management function (Disk-management function)
0DH - disk reset 2EH - set check mark
0EH - Select Disk 36H - Read Drive Assignment Information
19h - Read the current drive 54h - read the check mark
1BH, 1CH - Read the drive data
(1) Function 0DH
Function Description: Empty the current file buffer, but in MS-DOS, temporarily write the data of the buffer will write to disk entry parameters: AH = 0DH
Export parameters: no
(2) Function 0EH
Function Description: Specify the current drive
Entrance parameters: AH = 0EH
DL = drive letter (0 = a, 1 = b, ...)
Export parameters: Al = current drive letter in the system
(3), function 19h
Function Description: Take the current default drive letter
Entrance parameters: AH = 19h
Export Parameters: Al = Drive Number (0 = a, 1 = B, ...)
(4), function 1BH and 1CH
Function Description: Get allocation information of the drive
Entrance parameters: AH = 1BH - for the default drive
AH = 1ch - for any driver, DL = drive letter (0 = default, 1 = a, ...)
Export parameters: Al = 0ffh - failed, otherwise,
Al = number of sectors per cluster
DS: bx = ID byte address
CX = size of the physical sector (number of bytes)
DX = number of clusters of the drive
(5), function 2EH
Function Description: Setting / Clear Operation System Auto Read Inspection Sign
Entrance parameters: ah = 2EH
DL = 00H
Al = 00H - Clear this flag, 01H - Set this flag
Export parameters: no
(6), function 36h
Function Description: Take the information of the selected drive
Entrance parameters: ah = 36h
DL = Drive Number (0- Default, 1 = A, 2 = B, ...)
Export parameters: If the function call failed, ax = 0fffh, otherwise,
AX = number of sectors per cluster
BX = number of clusters available
CX = size of the physical sector (number of bytes)
DX = number of clusters in the drive
(7), function 54h
Function Description: Read the verification mark
Entrance parameters: AH = 54h
Export Parameters: Al = Current Test Sign Value: 00h - Off Test, 01H - Test
4, file operation function (File Operation function)
3ch - create a file
3DH - Open the file
3EH - Close the file
41h - Delete file
43H - Read / set file properties
45H - Copy file handle
46h - Redefile File Handle
4EH - Find the first file
4FH - Find the next file
56h - File name
57h - Date and time of reading / setting file
5ah - Create a temporary file
5bh - Creating a new file
67h - Set the number of file handles (maximum file number)
6ch - Extended Open File Function (Open, Create or Replace File)
(1), function 3ch
Function Description: Create a new file with the specified file name. If the specified file already exists, set its length of 0. After creation, the file is open and returns its handle.
Entrance parameters: ah = 3ch
DS: DX = Specifies the address of the file name string (with 0 is the end flag of the string)
CX = file properties (these flags can be combined) bits 0 = 1 - read-only
Bit 2 = 1 - System
Bit 5 = 1 - Archive bit 1 = 1 - implicit
Bit 3 = 1 - Volume Logo
Other positions are reserved, and set to 0
Export Parameters: CF = 0-- Create a success, ax = file handle, otherwise, AX = error number (03H, 04H or 05H), its meaning see the error code table (2), function 3DH
Function Description: Open the specified drive, path, and file name and return its file handle
Entrance parameters: ah = 3dh
DS: DX = Indicates the string of the file (with 0 is the end flag of the string)
Al is open mode: bit 0 ~ 2000-read-only mode 001 - write mode 010-read / write way
Bit 3 is reserved, its value is 0
Bit 4 ~ 6 shared mode 000- compatible mode 001- do not share 010- refuse to write
011- Refusing to read 100- Do not reject any operation
Bit 7 inheritance logo - 0/1: child process inherits or does not inherit handle
Export Parameters: CF = 0 - Open success, ax = file handle, otherwise, AX = error number (02H, 03H, 04H, 05H or 0CH), its meaning see the error code table
(3), function 3EH
Function Description: Turn off the file of the specified handle
Entrance parameters: ah = 3EH
BX = file handle
Export Parameters: CF = 0-- Close success, otherwise, AX = error number (06h), its meaning see the error code table
(4), function 41h
Function Description: Delete the specified file
Entrance parameters: AH = 41h
DS: DX = file name string address
Export parameters: cf = 0 - Delete success, otherwise, AX = error number (02H, 03H or 05H), its meaning see the error code table
(5), function 43h
Function Description: Read or set the properties of the specified file
Entrance parameters: AH = 43h
BX = file handle
DS: DX = file name string address
Al = 00H / 01H - Read / set file properties
CX = file attribute: bit 0 = 1 - read-only bit 1 = 1 - implicit
Bit 2 = 1 - System Bit 3 = 1 - Volume Logo
Bit 5 = 1 - Archive other positions are not available, and set to 0
Export Parameters: CF = 0-- Close success, cx = file attribute, otherwise, AX = error number (01H, 02H, 03H or 05H), its meaning see error code table
(6), function 45h
Function Description: Copy the handle of the currently open device or file, the handle corresponding to the same device or file
Entrance parameters: AH = 45h
BX = file handle to be replicated
Export parameters: cf = 0 - copy success, ax = new handle, otherwise, AX = error number (04H or 06H), its meaning see error code table
(7), function 46h
Function Description: Specify the two handles, point the second handle to the first handle, ie the second handle is redirected.
Entrance parameters: AH = 46h
BX = handle of files or devices
CX = to be redirected to file handle
Export parameters: cf = 0 - Redirect success, otherwise, AX = error number (04H or 06H), its meaning see error code table
(8), function 4EH
Function Description: Get the first file that matches the given file name
Entrance parameters: AH = 4EH
DS: DX = String of a given file name
CX = file attribute used when search: Bit 0 = 1 - Read-only bit 1 = 1 - Injection bit 2 = 1 - System Bit 3 = 1 - Volume Logo
Bit 4 = 1 - Contents 5 = 1 - Archive
Other positions are reserved, and set to 0
Export Parameters: CF = 1 - Operation Failure, AX = Error Number (02H, 03H or 12H), the meaning of the error code table, otherwise, the operation is successful, DTA (Disk Transfer
Area) Fill in data as follows: bytes 00 ~ 14h
Byte 15h matching file properties
Byte 16 ~ 17h compressed file name
Byte 18 ~ 19h compressed file date
Bytes 1A ~ 1DH file size
Byte 1e ~ 2ah file name string
(9), function 4FH
Function Description: After the function of the interrupt 21h is successfully used, search the next file name
Entrance parameters: AH = 4FH
Al = the code returned
Export Parameters: CF = 1 - Operation Failure, AX = Error Number (12H), its meaning see the error code table, otherwise, the operation is successful, the data in the DTA is shown in the front function 4EH
(10), function 56h
Function Description: File
Entrance parameters: AH = 56h
DS: DX = Current File Name String Address
ES: DI = New File Name String Address
Export Parameters: CF = 0-- Operation success, otherwise, AX = error number (02H, 03H, 05H, 11H), its meaning see the error code table
(11), function 57h
Function Description: Date and time of reading / setting file
Entrance parameters: AH = 57h
BX = file handle read date and time Al = 00H
Set the date and time Al = 01H
CX = Time (0F ~ 0BH: Hours, 0AH ~ 05H: Minutes, 04H ~ 00H: 2 seconds)
DX = Date (0F ~ 09H: Year (relative to 1980), 08h ~ 05H: Month, 04H ~ 00h: Day)
Export parameters: cf = 1 - Operation failed, ax = error number (01H, 06H), its meaning see the error code table, otherwise, if it is read file information, CX = time, dx = date
(12) Function 5ah
Function Description: Create a temporary file
Entrance parameters: ah = 5ah
DS: DX = pathname of path name
Cx = file attribute (bit can be combined), is defined as follows: Bit 0 = 1 Read bit 3-4 = 0 Reserved
Bit 1 = 1 implied bit 5 = 1 archive
Bit 2 = 1 System Bit 6-15 = 0 Reserved
Export Parameters: CF = 0 - Operation, AX = File Handle, DS: DX = Complete Path File Address, otherwise, AX = Error number (03H, 04H or 05H), its meaning see error code table
(13), function 5BH
Function Description: Create a new file
Entrance parameters: ah = 5bh
DS: DX = pathname of path name
CX = file attribute (bit can be combined), is defined as follows: Bit 0 = 1 read bit 4 = 0 reserved bit 1 = 1 implied bit 5 = 1 Archive
Bit 2 = 1 System Bit 6-15 = 0 Reserved
Bit 3 = 1 volume mark
Export Parameters: CF = 0 - Operation success, ax = file handle, otherwise, AX = error number (03H, 04H, 05H or 50H), its meaning see error code table
(14), function 67h
Function Description: Set the number of file handles (maximum file number)
Entrance parameters: AH = 67h
BX = number of handles
Export Parameters: CF = 0 - Successful operation, otherwise, AX = error number, its meaning see the error code table
(15), function 6ch
Function Description: Extended Open File Features (Open, Create or Replace File)
Entrance parameters: AH = 6ch
Al = 00H
DS: Si = pathname of path name
BX = Open mode 2 ~ 0000- read only 001- only write 010 - readable, write
Bit 3 Reserved (0)
Bit 6 ~ 4000-compatible 001- refuse to read and write 010 - refuse to write
011- Refusing to read 100 - do not reject any operation
Bit 70-child process inherits the handle, 1-child process does not inherit the handle
Bit 12 ~ 8 Reserved (0)
Bit 13 fatal error handler, 0-execute INT 24h, otherwise, return the error code to the process
Bit 14 Write: 0- Write buffer, 1-write files directly
Bit 15 Reserved (0)
Cx = file properties
Bit 0 = 1 read bit 4 = 0 retained
Bit 1 = 1 implied bit 5 = 1 archive
Bit 2 = 1 System Bit 6-15 = 0 Reserved
Bit 3 = 1 volume label
Dx = Open the flag 3 ~ 0 0 - Open failed, 1-open file, 2-replacement file
Bit 7 ~ 4 0 - Open failed, 1-creation file
Bit 15 ~ 8 0 - Reserved
Export Parameters: CF = 1 - Operation Fail, AX = Error Number, the meaning of the error code table, otherwise,
AX = file handle
CX = 1-- file existence, open
= 2 - The file does not exist, create it
5, File Operation Function (FCB) (File Operation Function)
0FH - Open the file 16h - Create a file
10h - Close File 17h - File
11h, 12h - Find the first or next file 23h - read the size of the file
13h - Delete File 29h - Analysis File Name
(1), function 0FH
Function Description: Open the file and make it ready to read / write well
Entrance parameters: AH = 0FH
DS: DX = Address of the file control block
Export parameters: Al = 00H - Open success, otherwise, Al = FFH (such as files can not find)
In the MS-DOS operating system, the fields of file control blocks are shown in the table below. Field name offset field meaning
Drive word 00h1 for Drive A, 2 for Drive B, ...
Current block field 0CH00H
Record the size field 0EH0080H
File length field 10h file byte
Date field 14H date
Time field 16h
(2), function 10h
Function Description: Close the file
Entrance parameters: AH = 10h
DS: DX = Address of the file control block
Export parameters: Al = 00H-- Close success, otherwise, Al = FFH (3), features 11h and 12h
Function Description: Find the first or next matching file
Entrance parameters: AH = 11h - the first matching file
= 12h - Next matching file
DS: DX = Address of the file control block
Export Parameters: Al = 00H - Find, otherwise, Al = FFH
(4), function 13h
Function Description: In the specified (or default) drive, delete all matching files
Entrance parameters: AH = 13h
DS: DX = Address of the file control block
Export parameters: Al = 00H - Delete success, otherwise, Al = FFH
(5), function 16h
Function Description: Create a file in the current directory, its file length is 0, and open the file, prepare for the subsequent read / write operation
Entrance parameters: AH = 16h
DS: DX = Undepended file control block address
Export Parameters: Al = 00H - Create success, otherwise, Al = FFH (eg disk full)
(6), function 17h
Function Description: In the current directory of the specified drive, all matching files are named
Entrance parameters: AH = 17h
DS: DX = Specify the address of the file control block
Export Parameters: Al = 00H - Successful, otherwise, Al = FFH
(7), function 23h
Function Description: Find a matching file in the current directory. If found, use its record number to update its file size
Entrance parameters: AH = 23h
DS: DX = Undepended file control block address
Export Parameters: Al = 00H - Matching Successfully, the field of the offset in the FCB is set to its record number, otherwise, Al = 0FFH
(8), function 29h
Function Description: Analyze a string (file name) to place different fields in the FCB table
Entrance parameters: AH = 29h
CX = number of records to write
DS: Si = address of the string segment
ES: DI = FCB address
Al = Analysis Control Sign Bit 3 = 1-- If there is a file suffix in the string, the file suffix in the FCB will change
= 0 - If the hyperfix is retrofitted, if there is no suffix after the analysis, the rest of the FCB is set to "empty"
Bit 2 = 1-- If there is a file name in the string, the file name in the FCB will change
= 0-- If the file name ignores the modification, if there is no file name after the analysis, the file name segment in the FCB is set to "empty"
Bit 1 = 1-- If the drive letter is specified in the string, the ID byte in the FCB is modified.
= 0-- If the ID byte ignores the modification, if the drive number is not specified after the analysis, the driver field in the FCB is set to 0 (default)
Bit 0 = 1--
= 0 - ignore the predecessor split
Do not ignore preamble split
Export Parameters: Al = 00H- No Tongzi Character 01H- Have Tongzi Character FFH-Drive No. illegal
DS: Si = Address of the first character after the analysis
ES: Di = after formatting, unopened FCB address
6, record operation function (Record function)
1AH - Set the data transfer area address 42H - Set the file pointer
2FH - Read Data Transmission Area Address 5ch - File Area Phase or Unlock 3FH - Read File or Device 68H - Submit File Buffer Data
40h - write file or equipment
(2), function 2FH
Function Description: Get the current address of DTA for FCB read / write operations
Entrance parameters: AH = 2FH
Export Parameters: ES: BX = DTA segment address and offset
(3), function 3FH
Function Description: Read the specified number byte from the previously opened file and move the file pointer
Entrance parameters: AH = 3FH
BX = file handle
CX = number of bytes to be read
DS: DX = Buffer Address of the Character
Export Parameters: CF = 0-- Read success, ax = the number of characters read, otherwise, AX = error number (05H or 06H), its meaning see error code table
(4), function 40h
Function Description: Write the previously opened file to the specified number of bytes, and modify the file pointer accordingly
Entrance parameters: ah = 40h
BX = file handle
CX = number of bytes written
DS: DX = buffer address of the storage data
Export Parameters: CF = 0-- Close success, AX = number of bytes written, otherwise, AX = error number (05H or 06H), its meaning see error code table
(5), function 42h
Function Description: Set the relative position of the file pointer (relative to the file header, file end and current location)
Entrance parameters: AH = 42h
BX = file handle
CX = high of offset
DX = low offset
Al = 00h - absolute offset from the file header
= 01H - Offset from the current file pointer (can be symbol)
= 02H - Offset from the end of the file (can be symbol)
Export Parameters: CF = 0-- Set success, DX is the high position of the pointer, AX is its low, otherwise, AX = error number (01h and 06h), the meaning of the error code table.
(6), function 5ch
Function Description: File area lock or unlock
Entrance parameters: AH = 5ch
Al = 00H-- Regional lock 01H - region unlock
BX = file handle
CX: DX = area offset
Si: Di = area length
DS: DX = pathname of path name
Export Parameters: CF = 0-- Operation success, otherwise, AX = error number (01H, 06H, 21H or 24h), its meaning see error code table
(7), function 68h
Function Description: Submit file buffer data
Entrance parameters: AH = 68H
BX = file handle
Export Parameters: CF = 0 - Successful operation, otherwise, AX = error number, its meaning see the error code table
7, record operation function (FCB) (Record function)
14h - sequential reading 24h - Set the number of relative records
15h - sequential written 27h - Random Read Block
21h - Random Read 28H - Random Writing Block
22h - Random Writing
(1), function 14h
Function Description: Read the next sequence block from the file and add a file corresponding to the file
Entrance parameters: AH = 14h
DS: DX = Open the address of the file control block
Export parameters: Al = 00H - Read success 01h-- file end
02H - Segment Wound 03H - Partial record in the end
(2), function 15h function description: write the next order data block to the file, and add a file corresponding to the file
Entrance parameters: AH = 15h
DS: DX = Open the address of the file control block
Export Parameters: Al = 00H - Write success 01H - Disk full 02H - segment 10
(3), function 21h
Function Description: Read the currently selected record from the file
Entrance parameters: AH = 21h
DS: DX = Open the address of the file control block
Export parameters: Al = 00H - Read success 01h-- file end
02H - Cancel reading operation 03h-- Partial record in the file
(4), function 22h
Function Description: Write data in memory in the currently selected record
Entrance parameters: AH = 22h
DS: DX = Open the address of the file control block
Export Parameters: Al = 00H- Write success 01H-disk full 02h- cancel write operation
(5), function 24h
Function Description: Sets the number of relative records in the FCB as the number of records opened in the FCB
Entrance parameters: AH = 24h
DS: DX = Open the address of the file control block
Export parameters: The value of Al is destroyed, other registers are not affected, the offset of the FCB is 21h units
(6), function 27h
Function Description: Read Several Records to Memory from the file
Entrance parameters: AH = 27h
DS: DX = Open the address of the file control block
Export parameters: Al = 00H - Read success 01h-- file end
02H - Cancel reading operation 03h-- Partial record in the file
Cx = number of records actually read
(7), function 28h
Function Description: Write several records from memory to files
Entrance parameters: ah = 28h
CX = number of records to write
DS: DX = Open the address of the file control block
Export Parameters: Al = 00H - Write success 01H - Disk full 02H - segment 10
CX = number of records actually written
8, memory allocation function (Memory-Allocation function)
48h - allocate memory block
49h - release memory block
4AH - Redefile the size of the memory block
58H - Read / set memory allocation strategy
(1), function 48h
Function Description: Assign a memory unit and return the first address of the memory cell
Entrance parameters: AH = 48h
BX = Number of memory cell bytes required to apply
Export Parameters: CF = 0 - Assignment Success, AX = The first address of the storage unit, otherwise, ax = error number (07h or 08h), the meaning of the error code table, BX = Maximum number of blocks available
(2), function 49h
Function Description: Release the memory unit block to use other programs
Entrance parameters: AH = 49h
ES = segment address of the application block
Export parameters: cf = 0 - release success, otherwise, AX = error number (07h or 09h), the meaning of the error code table
(3), function 4AH
Function Description: Dynamically change a memory block according to the needs of the program
Entrance parameters: ah = 4ah
BX = Need a new memory block size
ES = segment address of the modified block
Export Parameters: CF = 0-- Modify success, otherwise, AX = error number (07H, 08H or 09H), its meaning see error code table, bx = available maximum block size (4), function 58h
Function Description: Read / Set Memory Allocation Policy
Entry parameters: AH = 58h Read memory allocation strategy AL = 00H
Set the memory allocation policy AL = 01H
BX = memory allocation policy code:
00h- first satisfaction
01h- best satisfaction
02H- finally satisfied
Export Parameters: CF = 0-- Operation, AX = The memory allocation policy code (meaning as described above), otherwise, AX = error number (01H), its meaning see error code table
9. System function
25h - Set interrupt vector
30h - read the MS-DOS version number
33H - Read / set the Break Sign
34h - Read the address of the Indos logo
35H - Read interrupt vector
38H - Read / set national information
44H -IOCTL (I / O Control)
50H - Setup Block Prefix (PSP) Address
51H - Read Program Segment Prefix (PSP) Address
59h - Read the extension error message
5EH - Read the machine name, read / set the printer configuration
5FH - equipment redirection
63H - Read the front guide byte section
65h - Reading national information
66h - read / set the code page
5D0AH - Set an extension error message
(1), function 25h
Function Description: Set the interrupt vector table
Entrance parameters: ah = interrupt number
DS: DX = Initial address of the interrupt handler
Export parameters: no
(2), function 30h
Function Description: Take the version number of the MS-DOS operating system
Entrance parameters: AH = 30h
Export parameters: Al = 0 - V 1.0; other high versions are: Al = main version number
AH = time version number (MS-DOS 3.1 = 0ah, ...)
BH = OEM serial number (ORIGINAL Equipment Manufacture)
BL: CX = 24-bit user serial number
(3), function 33h
Function Description: Get or change the status of the operating system interrupt. During the function call, it will affect the detection of ^ c
Entrance parameters: ah = 33h
Al = 00h-- take state
= 01H-- Set state, DL = 00/01 indicates that the state OFF / ON
Export parameters: When the state is taken, DL = 00 / 01-- represents OFF / ON, respectively.
Description:
1. If other function numbers are stored in Al, the value of Al is 0ffh;
2, if Al is 5, start the drive letter to return in DL (1-A, 2-B, ...)
(4), function 34h
Function Description: Get the far address of the Indos flag, it is active when DOS maintenance means DOS
Entrance parameters: AH = 34h
Export Parameters: ES: BX = IndOS logo far address
If the unit value is 1, it means that the DOS function is executed, otherwise it is not.
(5), function 35h
Function Description: Take the entry address of the designated interrupt number
Entrance parameters: AH = 35H
Al = interrupt number
Export Parameters: ES: BX = Interrupt Handling Entrance Address
(6), function 38h
Function Description: Read or set national information
Entrance parameters: AH = 38h When reading country information, DS: DX = stores the address of the return information
Al = 0 - take the current national information
Al = 1 ~ 0FEH - Country information less than 255 countries
Al = 0FFH - Take a national information greater than or equal to 255, bx = national code
Set the national information
DX = 0fff
Al = 0 ~ 0FEH - set country information for country code less than 255
Al = 0FFH - set code greater than or equal to 255, bx = national code
Export parameters: cf = 0-- call success, bx = national code, otherwise. AX = Error Code (02H), the meaning of the error code table shows that the national information is as follows:
Bytes 0-1h: Date format: 0-mDy, 1-DMY, 2-YMD
Byte 2-6h: currency characters
Byte 7-8h: Numerican Segmentation
Byte 9-0AH: numerical precision split
Byte 0B-0CH: Daily Duringia
Byte 0D-0EH: Time Spacer
Byte 0FH: currency format
Bit 0 = 0 - The currency symbol is before, otherwise, the currency symbol is behind
Bit 1 = 0 - There is no space between currency symbols and data, otherwise there is a space between the two
Bit 2 = 0 - The currency symbol and the decimal point are separated, otherwise, the currency symbol replaces the decimal point.
Byte 10h: Currency decumeration
Bytes 11h: Time format. Bit 0 = 0-12 hours, otherwise, 24-hour system
Bytes 12 ~ 15h: Case-Map call address
Byte 16 ~ 17h: string splitter
Bytes 18 ~ 21h: Reserved
(7), function 44h
Function Description: Input / Output Control, its sub-function description:
00h- Take equipment information 01h- Take equipment information
02H- Accept control data 03H- Send control data to the character device driver from the character device driver
04h- from the block device driver accepts control data 05H- Send control data to block device driver
06h- Check Input Status 07h- Check Output Status
08H- Check if the block device is a detachable device 09h- check if the device is a remote device
0AH - Check the handle whether the handle is 0BH- change the number of shared access portals
General I / O control information of 0CH-character devices 0DH-block devices general I / O control information
0EH- Read logic drive mapping relationship 0FH- set logical drive mapping relationship
Description: 00h, 06h, and 07h in the input / output sub function are only for file handles, and network devices are not supported by subs factories 00h ~ 08h.
(8), function 50h
Function Description: Set the block prefix (PSP) address
Entrance parameters: AH = 50h
BX = new PSP address
Export parameters: no
(9), function 51h
Function Description: Read the program segment prefix (PSP) address
Entrance parameters: AH = 51H
Export Parameters: bx = PSP Address
(10), function 59h
Function Description: Read the extension error message
Entrance parameters: AH = 59h
BX = 00H
Export Parameters: AX = Extended Error Code, Its Meaning See Error Code Table
BH = error type, its definition is as follows: 01H- Resource shortage 02H- is in a temporary state rather than errors
03H-permission problem 04H-system software internal error
05H- hardware failure 06h- system software failed, but not active process failed
07H- Application error 08H- file or data item is not found
09H- file or data item type or format error 0AH- file or data item locks
Bad disk, disk in disk, disk in the drive 0CH- Other errors
BL = Measures adopted, it is defined as follows:
01H - After retrying several times, select "Termination" or "ignore"
02H - Retry several times (two times to wait), then select "Termination" or "ignore"
03h - Get the right information from the user
04h - Terminate the application and clear its resources
05h - Terminate the program immediately, but did not clear its resources
06h - ignore the error
07h - Eliminate the cause of the error, try again
CH = error location, is defined as follows:
01h - I don't know
02H - block device (disk or disk simulator)
03H - Network
04H - serial equipment
05H - memory
ES: DI = String of the disk label, if AX = 0022H (illegal change disks)
(11) Function 5EH
Function Description: Read the machine name, read / set the printer configuration subunit function description
00h read the machine name
02h sets the printer installation string
03H read the printer installation string
1, sub function 1
Entrance parameters: AH = 5EH
Al = 00H
DS: DX = Accept the address of the string buffer
Export Parameters: CF = 1 - Action Failure, AX = Error Number (01H), the meaning of the error code table, otherwise,
CH = 00h - machine name undefined, otherwise, the machine name is defined
CL = NetBios name (when CH ≠ 00h)
DS: DX = Identifier Address (when CH ≠ 00h)
2, sub function 2
Entrance parameters: AH = 5EH
Al = 02H
BX = redirect list index
CX = the length of the installation string
DS: Si = Address of the installation string
Export Parameters: CF = 0 - Operation success, otherwise, AX = error number (01H), the meaning of the error code table
3, sub-function 3
Entrance parameters: AH = 5EH
Al = 03H
BX = redirect list index
ES: DI = Accept the address of the string buffer
Export Parameters: CF = 0 - Operation success, CX = The length of the string, otherwise, AX = error number (01H), its meaning see the error code table
(12), function 5FH
Function Description: Device Redirection Sub Features Description
02h read redirect list index
03h redirection equipment
1, sub function 1
Entrance parameters: AH = 5FH
Al = 02H
BX = redirect list index
DS: Si = 16-byte storage area address of the local device name
ES: Di = 128-byte storage area address of the network name
Export Parameters: CF = 1 - Operation failure, AX = Error number (01H or 12H), the meaning of the error code table, otherwise, BH bit 0 = 0H-- equipment is legal, otherwise, the equipment is illegal
BL = Device type --03H: Printer, 04h: Drive
CX = storage parameter value
Dx = destroyed
BP = destroyed
DS: Si = Address of the local device name
ES: Di = Address of the network name
2, sub function 2
Entrance parameters: ah = 5Fhal = 03h
BL = Device type --03H: Printer, 04h: Drive
CX = Parameters saved by caller
DS: Si = 16-byte storage area address of the local device name
ES: Di = network name 128-byte storage area, followed by password
Export Parameters: CF = 0 - Operation success, otherwise, AX = error number (01H, 03H, 05H, 08H, 0FH or 12H), its meaning see the error code table
(13), function 63h
Function Description: Read the front lead byte section table
Entrance parameters: AH = 63h Al = Sub function
= 00h- Read the system front guide field table address
= 01H- Setting / Clear Temporary Console Sign (DL = 00H / 01H- Clear / Setting Sign)
= 02H- Read the temporary console flag value
Export parameters: bx = 1 - Operation failed, AX = error number (01H), its meaning see the error code table, otherwise, when calling,
If Al = 00h, then the DS: Si = System leadfield text;
If Al = 02h, then DL = Temporary Console Sign
(14), function 65H
Function Description: Read the extension country information
Entrance parameters: AH = 65H
BX = code page (-1 = active CON device)
CX = buffer size for accepting information
DX = national logo (-1 = default)
ES: DI = Buffer address of the information is Al = sub function
= 01H - Read the general national information
= 02H-- Read the pointer to the uppercase alphabet
= 04H - Read the pointer to the file name uppercase alphabet
= 06h - Read the pointer to the table
= 07h - Read pointer to DBCS vector
Export Parameters: CF = 0 - The operation is successful, the required data is stored in the buffer, otherwise, AX = error number (02H), the meaning of the error code table
(15), function 66h
Function Description: Read / Set Code
Entrance parameters: AH = 66h
Al = Sub function number: 01h-- Read code page, 02H - Select code page
BX = selected code page (when Al = 02h)
Export Parameters: CF = 0 - Operation success, when the tuning sub function is 01h, bx = active code page, DX = default code page, otherwise, AX = error number (02h or 65h), its meaning see error code table
(16), function 5D0AH
Function Description: Set an extension error message
Entrance parameters: AX = 5d0ah
DS: DX = Extended the address of the error structure, the description of this structure is as follows: Extend_err struct
RAX Word?; AX
RBX Word?; BX
RCX Word?; CX
RDX Word?; DX
RSI Word?; Si
RDI Word?; DI
RDS Word?; DS
RES Word?; ES
Pad Word 3 DUP (0)
Extend_ERRENDS
Export parameters: no
10. Process-control function 00h - termination process
26h - Creating a new program prefix (PSP)
31h - termination and residing
4BH - Execute Procedure (Exec)
4ch - Termination process with return code mode
4DH - Read Return Code
62H - Read the PSP address
(1), function 00H
Function Description: Termination Process. This is one of the methods of the termination process that can be used.
Entrance parameters: AH = 00H
CS = code segment address
Export parameters: no
(2), function 26h
Function Description: Copy the program segment prefix (PSP) currently executing the program to the specified address in the memory, and can change it for other programs.
Entrance parameters: AH = 26h
DX = segment address of the new program prefix
Export parameters: no
(3), function 31h
Function Description: Terminate the running of the program, pass a return code to its parent process, but part or all of the memory is in memory
Entrance parameters: ah = 31h
Al = Return code number
DX = number of bytes resides in memory
Export parameters: no
(4), function 4BH
Function Description: Executers (Exec)
Entrance parameters: ah = 4bh
ES: bx = address of the parameter block
DS: DX = Entrance address of the program
Al = 00h - loaded and executed, 03H - to put it in the form of coverage
Export Parameters: CF = 0-- Operation, other registers of other registers are destroyed, otherwise, AX = Error number (01H, 02H, 03H, 05H, 08H, 0AH or 0BH), its meaning See the wrong code table
(5), function 4ch
Function Description: Terminate the execution of the program and returns a code
Entrance parameters: AH = 4ch
Al = the code returned
Export parameters: no
(6), function 4DH
Function Description: The return code for the parent process gets the child process
Entrance parameters: AH = 4DH
Export parameters: AH = 00h-- with interrupt 20h, interrupt 21h function 0 or 4c normally terminated
= 01H - Users Press ^ C to terminate
= 02H-- Termination due to fatal errors
= 03H - Termination of the function of the interrupt 21h or the interrupt 27h
Al = sub-process return code: 00h - child process from interrupt 20h, interrupt 21h function 0 or 4c termination
(7), function 62h
Function Description: Read the PSP address
Entrance parameters: AH = 62H
Export parameters: bx = offset of PSP
11, time and date function (Time and Date function)
2AH - read date
2bh - set the date
2ch - read time
2DH - set time
(1), function 2AH
Function Description: Take the system date
Entrance parameters: ah = 2ah
Export parameters: cx = year (1980 ~ 2099), DH = month (1 ~ 12), DL = day (1 ~ 31)
Al = Week (0 = Sunday, 1 = Monday, ...)
(2), function 2BH
Function Description: Setting System Date
Entrance parameters: AH = 2BH
CX = year (1980 ~ 2099), DH = month (1 ~ 12), DL = day (1 ~ 31)
Export parameters: Al = 00H - Setting success, 0ffh - Settings failure (3), function 2ch
Function Description: Take the system time
Entrance parameters: AH = 2ch
Export parameters: CH = (0 ~ 23), CL = points (0 ~ 59), DL = seconds (0 ~ 59), Al = 100% seconds (0 ~ 99)
(4), function 2DH
Function Description: Setting System Time
Entrance parameters: AH = 2DH
CH = (0 ~ 23), CL = points (0 ~ 59), DL = seconds (0 ~ 59), Al =% seconds (0 ~ 99)
Export Parameters: Export Parameters: Al = 00H - Settings Success, 0FFH - Settings Failure
2, the mouse function interrupt INT 33h
00h - initialization mouse
01H - Show mouse pointer
02H - hidden mouse pointer
03H - Read the position of the mouse and its button
04H - Set the mouse pointer position
05H - Read mouse button information
06h - Read the mouse button release information
07h - Set the horizontal boundary of the mouse
08H - Set the mouse vertical border
09H - Set the graphic mouse shape
0AH - Set this article shape
0BH - Read the mouse movement count
0CH - Set the handler for the mouse event
0DH - Allowing light
0EH - Turn off the light
0FH - Set the mouse count and pixel ratio
10h - Set the mouse pointer hidden area
13h - Set the speed threshold
14H - Replace the mouse event interrupt
15h - Buffer size reading the mouse driver status
16h - Storage mouse drive status
17h - Reissue mouse driver status
18h - Set the replacement process for the mouse event
19h - Read the address of the replacement process
1AH - Set the sensitivity of the mouse
1BH - Read the sensitivity of the mouse
1CH - Set the rate of mouse breakage
1DH - Select the display page for the mouse pointer
1eh - Read the display page of the mouse pointer
1FH - Disable mouse driver
20H - Start the mouse driver
21h - Mouse driver reset
22h - Set the mouse driver information language
23h - reading language
24h - Read mouse information
25h - read the mouse driver information
26h - Read the maximum effective coordinate
(1), function 00H
Function Description: Initialize the mouse, this operation only needs to be executed
Entry parameters: ax = 00h
Export parameters: AX = 0000H - does not support mouse function, FFFFH - supports mouse function
BX = Mouse button (when supporting mouse function)
In the case where the mouse function is supported, the mouse is also set as the following parameters: 1, the mouse pointer is placed in the center of the screen
2. If the current mouse pointer is displayed, the mouse pointer is hidden after operation.
3, the display page of the mouse pointer is 0
4, display the mouse pointer according to the screen display mode: Text - Reverse display rectangular block, graphic - pointed shape
5, horizontal pixel ratio = 8: 8, vertical pixel ratio = 16: 8
6, set the horizontal and vertical display boundary for the current display mode maximum boundary
7, allow light to emulate
8, double speed threshold = 64
(2), function 01h
Function Description: Show mouse pointers, typically display its pointer with this function after the mouse is initialized
Entrance parameters: AX = 01h
Export parameters: no
(3), function 02h
Function Description: Hide mouse pointer, usually call this feature at the end of the program
Entrance parameters: AX = 02h
Export parameters: no
(4), function 03h
Function Description: Read the mouse position and its button status
Entrance parameters: AX = 03h
Export Parameters: BX = Button Status: Bit 0 = 1 - Press the left button 1 = 1 - Press the right button
Bit 2 = 1 - Press the middle button
Other bit - reserved, internal use
CX = horizontal position
DX = vertical position
(5), function 04h
Function Description: Set the mouse pointer position
Entrance parameters: AX = 04H, CX = horizontal position, DX = vertical position
Export parameters: no
(6), function 05h
Function Description: Read Mouse Button Information
Entry parameters: ax = 05h, bx = specified button: 0- left button, 1-right button, 2- Zhongkey
Export Parameters: AX = Button status, see the description of BX in 3H
BX = number of keys
CX = horizontal position (last button)
DX = vertical position (last button)
(7), function 06h
Function Description: Read Mouse Button Release Information
Entry parameters: ax = 06h, bx = specified button: 0- left button, 1-right button, 2- Zhongkey
Export Parameters: AX = Button status, see the description of BX in 3H
BX = number of releases
CX = horizontal position (last release)
DX = vertical position (last release)
(8), function 07h
Function Description: Set the horizontal boundary of the mouse
Entrance parameters: AX = 07h
CX = minimum horizontal position
DX = maximum horizontal position
Export parameters: None, mouse may automatically move into the new area due to new areas
(9), function 08h
Function Description: Set the mouse vertical boundary
Entrance parameters: AX = 08h
CX = minimum vertical position
DX = maximum vertical position
Export parameters: None, mouse may automatically move into the new area due to new areas
(10), function 09h
Function Description: Set a graphic mouse shape
Entrance parameters: AX = 09h
BX = horizontal position
Cx = vertical position of the pointer
ES: DX = 16 × 16-bit cursor image address parameter description: (bx, cx) is the position of the mouse pointer in 16 × 16 dot matrix, (0, 0) is the upper left corner;
ES: DX Points 16 × 16-point bit image hidden codes in the memory cells, followed by a 16 × 16 lattice cursor mask.
Display method of mouse pointer: bit image hidden code "Logic" on the screen display area, and then use the cursor mask content "different or" the result of the previous operation.
Export parameters: no
(11), function 0AH
Function Description: Set the shape of this article
Entrance parameters: AX = 0ah
BX = Cursor Type: 0 -CX and DX all the meaning as follows: Bit 7 ~ 0 Mouse pointer symbol
Bit 10 ~ 8 characters foreground
Bit 11 brightness
Bit 14 ~ 12 character background color
Bit 15 flashes
1 -CX = start scan line of cursor
DX = end scan line of cursor
Export parameters: no
(12), function 0BH
Function Description: Read the mouse movement count
Entrance parameters: AX = 0bh
Export parameters: cx = horizontal moving distance: positive - move right, negative number - move left
DX = Vertical Move Distance: Positive - Move down, Negative - Move
(13), function 0ch
Function Description: Set the handler for the mouse event
Entrance parameters: AX = 0CH
CX = interrupt mask bit 0 = 1 - mouse pointer position transmission change
Bit 1 = 1 - Press the left button
Bit 2 = 1 - Release Left button
Bit 3 = 1 - Press the right button
Bit 4 = 1 - Release the right button
Bit 5 = 1 - Press the intermediate button
Bit 6 = 1 - Release the intermediate button
Bit 7 ~ 15 = 0 - retain
ES: DX = Interrupt handler address
When entering an interrupt handler, the value of the register is in the case:
AX = interrupt mask
BX = button status
CX = horizontal position of mouse pointer
Dx = vertical position of mouse pointer
Si = change in horizontal position
Di = variation in vertical position
Export parameters: no
(14), function 0DH
Function Description: Allowing light in emulation
Entrance parameters: AX = 0DH
Export parameters: no
(15), function 0EH
Function Description: Turn off the emperor
Entrance parameters: AX = 0EH
Export parameters: no
(16), function 0FH
Function Description: Set the mouse count and pixel ratio
Entrance parameters: AX = 0FH
CX = horizontal proportion
DX = vertical ratio
Export parameters: no
(17), function 10h
Function Description: Set the mouse pointer hidden area
Entrance parameters: AX = 10h
CX = left upper corner X coordinate
Dx = left upper corner Y coordinate
Si = lower right angle X coordinate
Di = upper right corner Y coordinate
Export parameters: no
(18), function 13h
Function Description: Set the speed threshold, its default value is 64
Entrance parameters: ax = 13h
Dx = threshold
Export parameters: no
(19), function 14h
Function Description: Replace the mouse event interrupt
Entrance parameters: ax = 14h
CX = interrupt mask
ES: DX = Interrupt handler address
Export parameters: cx = old interrupt mask
ES: DX = old interrupt handler address
(20), function 15h
Function Description: Read the size of the buffer size of the mouse driver
Entrance parameters: AX = 15h
Export Parameters: bx = Size of the buffer required to store the mouse driver status
(21), function 16h
Function Description: Storage Mouse Drive Status
Entrance parameters: AX = 16h
ES: DX = Address for storing the status of the mouse drive
Export parameters: no
(22), function 17h
Function Description: Reissue Mouse Drive Status
Entrance parameters: AX = 17h
ES: DX = address of the mouse drive status
Export parameters: no
(23), function 18h
Function Description: Set an optional handler for the mouse event
Entrance parameters: AX = 18h
CX = replacement interrupt mask
ES: DX = Replace the address of the interrupt handler
Cf = 0
Export parameters: no
(24), function 19h
Function Description: Read the address of the replacement processor
Entrance parameters: AX = 19h
CX = replacement interrupt mask
Export Parameters: If AX = -1 - Unsuccessful, otherwise, es: dx = interrupt handler address
(25), function 1AH
Function Description: Set the sensitivity of the mouse, which is 1 ~ 100
Entrance parameters: ax = 1ah
BX = horizontal sensitivity (number of moving per 8 quadrants, general 8)
CX = Vertical sensitivity (number of moving per 8 quadrants, general 16)
DX = multiplier threshold
Export parameters: no
(26), function 1BH
Function Description: Read the sensitivity of the mouse
Entrance parameters: AX = 1BH
Export parameters: bx = horizontal sensitivity
CX = vertical sensitivity
DX = multiplier threshold
(27), function 1ch
Function Description: Set the mouse interrupt rate
Entrance parameters: AX = 1CH
BX = number of interruptions per second: 0 - Off interrupt, 1-30 / s, 2-50 / s, 3-100 / s, 4-200 / s
Export parameters: no
(28), function 1DH
Function Description: Select the display page for the mouse pointer
Entrance parameters: AX = 1DH
BX = display page
Export parameters: no
(29), function 1EH
Function Description: Read the display page of the mouse pointer
Entrance parameters: AX = 1EH
Export parameters: bx = display page
(30), function 1FH
Function Description: Disable mouse driver
Entrance parameters: AX = 1FH
Export Parameters: If AX = -1 - Unsuccessful, otherwise, the ES: bx = the address of the mouse driver
(31), function 20h
Function Description: Start the mouse driver
Entrance parameters: AX = 20h
Export parameters: no
(32), function 21h
Function Description: Mouse Driver Reset
Entry parameters: AX = 21h
Export Parameters: If AX = -1 - Unsuccessful, otherwise, BX = 2
(33), function 22h
Function Description: Set the mouse driver information language
Entrance parameters: AX = 22h
BX = language code: 0- English, 1-French, 2-Dutch, 3-German, 4-Swedish, 5-Finnish, 6-Spanish, 7-Portuguese, 8-Italian
Export parameters: no
(34), function 23h
Function Description: Read language
Entrance parameters: ax = 23h
Export parameters: bx = language code
(35), function 24h
Function Description: Read Mouse Information
Entrance parameters: AX = 24h
Export Parameters: BH = Home version number, BL = Acupbook number
CL = Interrupt request number
CH = mouse type: 1-bus mouse, 2-Serial Mouse, 3-Inport Mouse, 4-PS / 2 Mouse, 5-HP Mouse
(36), function 25h
Function Description: Read Mouse Driver Information
Entry parameters: ax = 25h
Export Parameters: AX = Mouse Driver Information: Bit 15 --0: Driver is .sys file, otherwise, for.comcom file
Bit 14--0: Incomplete mouse display driver, otherwise, for complete
Bit 13-12--00: Software Text Cursor
01: Hardware Text Cursor
1x: graphic cursor
(37), function 26h
Function Description: Read the maximum effective coordinate
Entrance parameters: AX = 26h
Export parameters: bx = mouse driver status
CX = maximum horizontal coordinate
DX = maximum vertical coordinates
3, other DOS interrupts
INT 20H - Termination Operation
INT 22H - Termination of the address of the process
INT 23H -CTRL C handler
INT 24h - fatal error handler
INT 25H - Read disk sector (ignore logical structure)
INT 26H - Write disk sector (ignore logical structure)
INT 27h - termination and resides in memory
INT 28h-DOS idle
INT 2FH - multiple interrupt service
(1), interrupt INT 20H
Function Description: Terminate the currently running program, it is one of several termination programs
Entry parameters: segment address of CS = PSP
Export parameters: no
(2), interrupt INT 22h
Function Description: Terminate the address of the handler, which is placed in the unit of 0AH ~ 0DH of the PSP before the program is loaded. The interrupt instruction is never written directly in the program.
(3), interrupt INT 23h
Function Description: CTRL C handler. The interrupt instruction is never written directly in the program.
(4), interrupt INT 24h
Function Description: Fatal Error handler. The interrupt instruction is never written directly in the program.
(5), interrupt INT 25h
Function Description: Absolute reading disk, reading data directly from logic devices into memory cells
Entrance parameters: Al = drive 号 (0 = a, 1 = b, ...) partition capacity ≤32m, there is: CX = number of sectors read
Dx = number of start sectors
DS: bx = store the address of the data buffer
Otherwise, there are: cx = -1
The address of the DS: bx = parameter block buffer, the structure of the parameter block is as follows: byte description
00 ~ 03H32 sector number
The number of sectors that will be read from 04 to 05h
The offset of the buffer storage of data 06 ~ 07H
Segment address of the buffer of data in 08 ~ 09H
Export Parameters: CF = 0 - Operation Success, otherwise, AX = error number, the meaning of the error, the error code table error code error meanings
80h attachment response failed
40h positioning operation failed
20h equipment controller failed
10h data fault (wrong CRC)
08h DMA failed
The sector required for 04h did not find
02H error address mark
01h error command
(6), int 26h
Function Description: Absolute Writing Disk, write directly in the memory cell to logic devices
Entrance parameters: consistent with the previous INT 25H
Export parameters: consistent with the previous INT 25H
(7), INT 27h
Function Description: Termination, and reside in memory
Entry parameters: CS = PSP segment value
DX = The offset of the last byte of the protected program plus 1
Export parameters: no
(8), int 28h
Function Description: DOS Idle Interrupt
Entrance parameters: no
Export parameters: no
(9), int 2fh
Function Description: Multi-interrupt service allows multiple resident programs to communicate with other processes through a single interrupt.
Entry parameters: AH = identification number, Al = function number, function number and its meaning as follows: Features function description
01H Spool printing
06h resides an assign command
10h stationed with Share command
B7H resident Append command
Export Parameters: If the inlet Al is 0, the exit Al = 0ffh, otherwise, its value depends on the handler BIOS interrupt:
1, display service (Video Service - INT 10H)
00h - set display mode 0ch - write image font
01H - Set the cursor shape 0DH - reading image
02H - Set the cursor position 0EH - display characters in TeleType mode
03H - Read Cursor Information 0FH - Read Display Mode
04H - Read the light pen position 10h - color
05H - Set display page 11h - font
06H, 07H - Initialization or scrolling 12H - Display configuration
08H - The characters at the cursor and its properties 13h - display strings in TeleType mode
09H - Press the specified property display character 1AH - Read / Set Display Combination Coding
0ah - Display character 1bh - Read function / status information at the current cursor
0BH - Set the palette, background color or border 1ch - save / restore the display status
(1), function 00H
Function Description: Set the display mode
Entrance parameters: AH = 00H
Al = Display mode, see below
Export parameters: no
The available display mode is listed below:
Display mode display mode property display mode display mode properties
00h40 × 2516 color text 01H40 × 2516 color text
02H80 × 2516 color text 03h80 × 2516 color text
04H320 × 2004 color 05H320 × 2004 colors
06H640 × 2002 color 07h80 × 252 color text
08H160 × 20016 color 09H320 × 20016 colors
0AH640 × 2004 color 0BH reserved
0CH retains 0DH320 × 20016 colors
0EH640 × 20016 color 0FH640 × 3502 (monochrome)
10h640 × 3504 color 10H640 × 35016 colors
11H640 × 4802 color 12H640 × 48016 colors
13H640 × 480256 colors
For super VGA display cards, we can use AX = 4F02H and the value of the following BX to set its display mode.
BX Display Mode Properties BX Display Mode Properties
100H640 × 400256 color 101H640 × 480256 colors
102H800 × 60016 color 103H800 × 600256 colors
104H1024 × 76816 color 105H1024 × 768256 colors
106H1280 × 102416 color 107H1280 × 1024256 colors
108H80 × 60 text mode 109H132 × 25 text mode
10AH132 × 43 Text Mode 10BH132 × 50 Text Mode
10ch132 × 60 text mode
(2), function 01h
Function Description: Set the cursor shape
Entrance parameters: AH = 01H
CH low four digits = starting line of cursor
CL low four = the end of the cursor
Export parameters: no
(3), function 02h
Function Description: Set the cursor location with the text coordination
Entrance parameters: ah = 02h
BH = display page number
DH = line (Y coordinate)
DL = column (X coordinate)
Export parameters: no
(4), function 03h
Function Description: Under the text coordinates, read the various information of the cursor
Entrance parameters: AH = 03H
BH = display page number
Export parameters: CH = starting line of cursor
CL = termination line of cursor
DH = line (Y coordinate)
DL = column (X coordinate)
(5), function 04h
Function Description: Get the current status and the pen position
Entrance parameters: ah = 04h
Export parameters: AH = 00H - Optical pen is not pressed / not triggered, 01H - The pen has been pressed / triggered
BX = pixel column (graphic X coordinate)
CH = pixel row (graphic y coordinate, display mode: 04h ~ 06h)
CX = pixel row (graphic y coordinate, display mode: 0DH ~ 10h) DH = character line (text Y coordinate)
DL = character column (text X coordinate)
(6), function 05h
Function Description: Set the display page, select the display page for the event
Entrance parameters: AH = 05H
Al = display page
For CGA, EGA, MCGA, and VGA, its display page is listed in the following table: Mode Page Number Display Type
00h, 01H0 ~ 7CGA, EGA, MCGA, VGA
02H, 03H0 ~ 3CGA
02H, 03H0 ~ 7EGA, MCGA, VGA
07H0 ~ 7EGA, VGA
0DH0 ~ 7EGA, VGA
0EH0 ~ 3EGA, VGA
0FH0 ~ 1EGA, VGA
10H0 ~ 1EGA, VGA
For PCJR:
Al = 80H - read the CRT / CPU page register
81H - Set the CPU page register
82H - Set the CRT page register
83H - Set the CRT / CPU page register
BH = CRT page (sub-function number 82h and 83h)
BL = CPU page (sub-function number 81h and 83h)
Export Parameters: For the former, there is no exit parameters, but under the call for PCJR at child function 80h ~ 83h, there is: BH = CRT page register, BL = CPU page register
(7), function 06h and 07h
Function Description: Initialization Screen or Rolling
Entrance parameters: AH = 06H - Up rolling screen, 07h - downward scroll
Al = Scroll line count (0 - Qing window)
BH = default attributes in blank area
(CH, CL) = the left upper corner position of the window (Y coordinate, X coordinate)
(DH, DL) = Window's lower right corner position (Y coordinate, X coordinate)
Export parameters: no
(8), function 08h
Function Description: Character and its properties at the read cursor
Entrance parameters: ah = 08h
BH = display page number
Export Parameters: AH = Property
Al = characters
(9), function 09h
Function Description: Display characters by specifying attributes at the current cursor
Entrance parameters: AH = 09h
Al = characters
BH = display page number
BL = attribute (text mode) or color (graphics mode)
Cx = number of times of repeating output characters
Export parameters: no
(10), function 0AH
Function Description: Display characters in the original cursor at the current cursor
Entrance parameters: AH = 0ah
Al = characters
BH = display page number
BL = color (graphics mode, only for PCJR)
Cx = number of times of repeating output characters
Export parameters: no
(11), function 0BH
Function Description: Set the palette, background color or border
Entrance parameters: ah = 0bh
Set color: BH = 00h, BL = color
Select palette: BH = 01H, BL = palette (320 × 200, 4 color graphics mode)
Export parameters: no
(12), function 0ch
Function Description: Write the image pixel
Entrance parameters: ah = 0ch
Al = pixel value
BH = page number
(CX, DX) = Graphic Sitting Label (X), Line (Y)
Export parameters: no
(13), function 0DH
Function Description: Read the image pixel
Entrance parameters: AH = 0DH
BH = page number
(CX, DX) = Graphic Sitting Label (X), Line (Y) Outlet Parameters: Al = Pixel Value
(14), function 0EH
Function Description: Display characters in TeleType mode
Entrance parameters: AH = 0EH
Al = characters
BH = page number
BL = foreground color (graphics mode)
Export parameters: no
(15), function 0FH
Function Description: Read Display Mode
Entrance parameters: AH = 0FH
Export parameters: AH = number of screen characters
Al = Display mode (see instructions in the function 00h)
BH = page number
(16), function 10h
Function Description: Color interrupt. The subfunction is as follows: Function number sub function name function number subsystem name
00h - Set the palette register 01h - set the border color
02H - Set the palette and border 03H - Trigger flashing / bright
07H - Read the palette register 08h - Read the border color
09H - Read the palette and border 10h - Set color register
12h - Set color register block 13h - Set color page status
15h - Read Color Register 17h - Read Color Register Block
1AH - Read color page status 1BH - Set grayscale value
(17), function 11h
Function Description: The font is interrupted. Its sub-function is as follows: Sub-function number function name
00h loading user font and programmable controller
10h loading user font and programmable controller
01H load 8 × 14 ROM font and programmable controller
11h loading 8 × 14 ROM font and programmable controller
02h load 8 × 8 ROM font and programmable controller
12h load 8 × 8 ROM font and programmable controller
03h set block indicator
04H load 8 × 16 ROM font and programmable controller
8 × 16 ROM font and programmable controller
20h set int 1fh font pointer
21h Set INT 43H for User Font
22h is 8 × 14 ROM font setting INT 43H
23h is 8 × 8 ROM font setting INT 43H
24h is 8 × 16 ROM font setting INT 43H
30h read font information
(18), function 12h
Function Description: The configuration interrupt of the display. The subfunction is as follows: Function number function name function number function name
10h - Read Configuration Information 20H - Select Screen Print
30H - Setting the scan line 31h - Allow / prohibit loading the default palette
32H - Allow / disabled 33H - Allow / prohibiting grayscale sum
34H - Allow / prohibition cursor simulation 35H - Switching activity display
36h - Allow / disable screen refresh
(19), function 13h
Function Description: Display strings in TELETYPE mode
Entrance parameters: AH = 13h
BH = page number
BL = attribute (if Al = 00h or 01h)
CX = display string length
(DH, DL) = coordinate (line, column)
ES: BP = Display String Address Al = Display Output Method
0-- Only the display character is included in the string, which shows the properties in the BL. After the display, the cursor position is constant
1 - The string contains only the display character, which shows the properties in the BL. After display, the cursor position changes
2 - String contains display characters and display properties. After the display, the cursor position is constant
3 - The string contains the display character and display attributes. After display, the cursor position changes
Export parameters: no
(20), function 1AH
Function Description: Read / Set the display combination encoding, only PS / 2 is valid, here
(21), function 1BH
Function Description: Read function / status information, only PS / 2 is valid, here is omitted
(22), function 1ch
Function Description: Save / Recovery Display Status, only PS / 2 is valid, here from this
2, Direct Disk Service (Direct Disk Service - INT 13H) 00h - Disk System Reset 0EH - Read Demoller Buffer
01H - Read Disk System Status 0FH - Write Sector Buffer
02H - Reading Demon 10H - Read Drive Status
03H - Writing Demo 11H - Calibrate Drive
04H - inspection sector 12h - controller RAM diagnosis
05H - Formatted track 13H - controller drive diagnosis
06H - formatted bad track 14H - internal diagnosis of controller
07H - Format Drive 15h - Read Disk Type
08H - Read driver parameter 16h - read disk change status
09H - Initializing hard disk parameter 17h - Set disk type
0AH - Read Long Distance 18H - Set Format Media Type
0BH - Write long sector 19H - magnetic head protection
0CH - Search 1AH - Format ESDI Drive
0DH - hard disk system reset
(1), function 00H
Function Description: Disk System Reset
Entrance parameters: AH = 00H
DL = drive, 00h ~ 7FH: floppy disk; 80h ~ 0ffh: hard disk
Export Parameters: CF = 0 - Operation, AH = 00h, otherwise, AH = status code, see the function number 01h
(2), function 01h
Function Description: Read disk system status
Entrance parameters: AH = 01H
DL = drive, 00h ~ 7FH: floppy disk; 80h ~ 0ffh: hard disk
Export Parameters: AH = 00h, Al = Status Code, is defined as follows:
00h - no error 01h - illegal order
02H - Address target does not find 03h - disk write protection (floppy disk)
04H - no found 05h - Reset failed (hard disk)
06H - Flood Disk Removing (Floppy Disk) 07H - Error Parameters Table (Hard Disk)
08H - DMA Crossing (floppy disk) 09H - DMA more than 64K limit
0AH - Wrong sector logo (hard disk) 0BH - Error track logo (hard disk)
0CH - Medium Type Unsometric (floppy disk) 0DH - formatted illegal sector number (hard disk)
0EH - Control data address target is discovered (hard disk) 0FH - DMA arbitration offshore (hard disk)
10h - Incorrect CRC or ECC Code 11H - ECC Correction Data War (Hard Disk)
CRC: CYCLIC Redundancy Check Code
ECC: Error Checking & Correcting Code
20H - Controller Failure 40h - Find failed
80H - Disk timeout (unarined) AAH - drive is not ready (hard disk)
BBH - Unselected error (hard disk) CCH - write error (hard disk)
E0H - status register error (hard disk) FFH - detection operation failed (hard disk)
(3), function 02h
Function Description: Reading Demo
Entrance parameters: ah = 02h
Al = number of sectors
CH = cylinder
CL = sector
DH = magnetic head
DL = drive, 00h ~ 7FH: floppy disk; 80h ~ 0ffh: hard disk
ES: bx = address of the buffer
Export Parameters: CF = 0 - Operation Success, AH = 00h, Al = Send number, otherwise, AH = status code, see the function number 01h
(4), function 03h
Function Description: Writing Demo
Entrance parameters: AH = 03H
Al = number of sectors
CH = cylinder
CL = sector
DH = magnetic head
DL = drive, 00h ~ 7FH: floppy disk; 80h ~ 0ffh: hard disk ES: bx = buffer address
Export Parameters: CF = 0 - Operation Success, AH = 00h, Al = Send number, otherwise, AH = status code, see the function number 01h
(5), function 04h
Function Description: Inspection Sector
Entrance parameters: ah = 04h
Al = number of sectors
CH = cylinder
CL = sector
DH = magnetic head
DL = drive, 00h ~ 7FH: floppy disk; 80h ~ 0ffh: hard disk
ES: bx = address of the buffer
Export Parameters: CF = 0 - Operation, AH = 00h, Al = The number of sectors is checked, otherwise, the AH = state code, see the function number 01h
(6), function 05h
Function Description: Format Catholic
Entrance parameters: AH = 05H
Al = Alternation (Interleave)
CH = cylinder
DH = magnetic head
DL = drive, 00h ~ 7FH: floppy disk; 80h ~ 0ffh: hard disk
ES: bx = address of the address domain list
Export Parameters: CF = 0 - Operation, AH = 00h, otherwise, AH = status code, see the function number 01h
(7), function 06h
Function Description: Format Decoction
Entrance parameters: AH = 06h
Al = alternate
CH = cylinder
DH = magnetic head
DL = 80H ~ 0FFH: Hard Disk
ES: bx = address of the address domain list
Export Parameters: CF = 0 - Operation, AH = 00h, otherwise, AH = status code, see the function number 01h
(8), function 07h
Function Description: Format The drive
Entrance parameters: AH = 07h
Al = alternate
CH = cylinder
DL = 80H ~ 0FFH: Hard Disk
Export Parameters: CF = 0 - Operation, AH = 00h, otherwise, AH = status code, see the function number 01h
(9), function 08h
Function Description: Read Drive Parameters
Entrance parameters: ah = 08h
DL = drive, 00h ~ 7FH: floppy disk; 80h ~ 0ffh: hard disk
Export Parameters: CF = 1 - Operation Failure, AH = Status Code, see the instructions in the function number 01h, otherwise, BL = 01H - 360K
= 02H - 1.2M
= 03H - 720K
= 04H - 1.44M
CH = low number of cylinders
CL bit 7-6 = 2 digits of the number of cylinders
CL bit 5-0 = number of sectors
DH = number of magnetic heads
DL = number of drivers
ES: DI = Disk drive parameter table address
(10), function 09h
Function Description: Initializing the hard disk parameters
Entrance parameters: AH = 09h
DL = 80H ~ 0FFH: Hard disk (there is also a problem with parameter table, here)
Export Parameters: CF = 0 - Operation, AH = 00h, otherwise, AH = status code, see the function number 01h
(11), function 0AH
Function Description: Read the long sector, each sector with four bytes of ECC encoding
Entrance parameters: AH = 0ah
Al = number of sectors
CH = cylinder
CL = sector
DH = magnetic head
DL = 80H ~ 0FFH: Hard Disk
ES: bx = address of the buffer
Export Parameters: CF = 0 - Operation Success, AH = 00h, Al = Send number, otherwise, AH = status code, see the function number 01h
(12), function 0BH
Function Description: Write the long sector, each sector with four bytes of ECC encoding
Entrance parameters: ah = 0bh
Al = number of sectors
CH = cylinder
CL = sector
DH = magnetic head
DL = 80H ~ 0FFH: Hard Disk
ES: bx = address of the buffer
Export Parameters: CF = 0 - Operation Success, AH = 00h, Al = Send number, otherwise, AH = status code, see the function number 01h
(13), function 0ch
Function Description: Search
Entrance parameters: ah = 0ch
CH = low 8 positions
CL (7-6) = high 2 in the cylinder
DH = magnetic head
DL = 80H ~ 0FFH: Hard Disk
Export Parameters: CF = 0 - Operation, AH = 00h, otherwise, AH = status code, see the function number 01h
(14), function 0DH
Function Description: Hard disk system reset
Entrance parameters: AH = 0DH
DL = 80H ~ 0FFH: Hard Disk
Export Parameters: CF = 0 - Operation, AH = 00h, otherwise, AH = status code, see the function number 01h
(15), function 0EH
Function Description: Reading Demon Buffer
Entrance parameters: AH = 0EH
ES: bx = address of the buffer
Export Parameters: CF = 0 - Operation, otherwise, AH = status code, see the function number 01h
(16), function 0FH
Function Description: Writing sector buffer
Entrance parameters: AH = 0FH
ES: bx = address of the buffer
Export Parameters: CF = 0 - Operation, otherwise, AH = status code, see the function number 01h
(17), function 10h
Function Description: Read Drive Status
Entrance parameters: AH = 10h
DL = 80H ~ 0FFH: Hard Disk
Export Parameters: CF = 0-- Operation, AH = 00h, otherwise, AH = status code, see the description in the function number 01h (18), function 11h
Function Description: Calibration Drive
Entrance parameters: AH = 11h
DL = 80H ~ 0FFH: Hard Disk
Export Parameters: CF = 0 - Operation, AH = 00h, otherwise, AH = status code, see the function number 01h
(19), function 12h
Function Description: Controller RAM Diagnostics
Entrance parameters: AH = 12h
Export Parameters: CF = 0 - Operation, otherwise, AH = status code, see the function number 01h
(20), function 13h
Function Description: Controller Drive Diagnosis
Entrance parameters: AH = 13h
Export Parameters: CF = 0 - Operation, otherwise, AH = status code, see the function number 01h
(21), function 14h
Function Description: Internal diagnosis of controller
Entrance parameters: AH = 14h
Export Parameters: CF = 0 - Operation, otherwise, AH = status code, see the function number 01h
(22), function 15h
Function Description: Read Disk Types
Entrance parameters: AH = 15h
DL = drive, 00h ~ 7FH: floppy disk; 80h ~ 0ffh: hard disk
Export parameters: cf = 1 - Operation failed, AH = state code, see the description in the function number 01h, otherwise, AH = 00h - no drive
= 01H - Floppy drive supported without changing lines
= 02H - Floppy drive supported with changing lines
= 03H - Hard disk, CX: DX = 512 bytes number
(23), function 16h
Function Description: Read Disk Change Status
Entrance parameters: AH = 16h
DL = 00H ~ 7FH: floppy disk
Export Parameters: CF = 0 - Disk is not changed, AH = 00h, otherwise, AH = 06h, see the function number 01h
(24), function 17h
Function Description: Set disk type
Entrance parameters: AH = 17h
DL = 00H ~ 7FH: floppy disk AL = 00h - unused
= 01H - 360K in the 360k drive
= 02H - 360K in the 1.2M drive
= 03H - 1.2M in the 1.2M drive
= 04H - 720K in the 720K drive
Export Parameters: CF = 0 - Operation success, AH = 00h, otherwise, AH = state encoding, see the function number 01h
(25), function 18h
Function Description: Set the formatting media type
Entrance parameters: AH = 18h
CH = cylindrical number
CL = number of sectors per track
DL = 00H ~ 7FH: floppy disk
Export Parameters: CF = 0 - Operation, AH = 00h, ES: DI = Media Type Parameter Table Address, otherwise, AH = State Code, see the function number 01h (26), function 19h
Function Description: The head protection is only valid in PS / 2, here from this
(27), function 1AH
Function Description: Format the ESDI drive, which is only valid in PS / 2, here from this
3, serial port service (Serial Port Service - INT 14H)
00h - initialization communication port 03H - Read communication port status
01H - Output Character 04H - Expansion Initial Communication Port
02H - Read the character from communication port
(1), function 00H
Function Description: Initialization Communication Port
Entrance parameters: AH = 00H
DX = Initialization communication slogan (0 = COM1, 1 = COM2, ...)
Al = Initialization parameters, the parameters are as follows: the number of bits of the baud rate parity stop bit
76543210
000 = 110x0 = none0 = 1 bit10 = 7 bits
001 = 15001 = ODD1 = 2 bits11 = 8 bits
010 = 30011 = Even
011 = 600
100 = 1200
101 = 2400
110 = 4800
111 = 9600
For PS / 2, it is possible to initialize its communication rate greater than 9600 using INT 14H.
Export parameters: AH = communication port status, the meaning of each status bit is 1: Bit 7 - Timeout
Bit 6-Transmission Shift Register is empty
Bit 5-Pass hold register is empty
Bit 4- Discovery Termination 3 - Discover Frame Error
Bit 2- Discover parity
Bit 1 - Discover the more item
Bit 0- Accept data is ready
Al = modem status
Bit 7-Accept single signal diagnosis
Bit 6-ring indicator
Bit 5-data transmission is ready
Bit 4 - Clear the data, re-transmit bit 3 - change the signal diagnosis on the receiving line
Bit 2-rear boundary ring indicator
Bit 1 - Change "Data Preparation" Status
Bit 0- Change "Clear - Send" Status
(2), function 01h
Function Description: Output characters to the communication port
Entrance parameters: AH = 01H
Al = characters
DX = Initialization communication slogan (0 = COM1, 1 = COM2, ...)
Export Parameters: The value of Al constantly
AH bit 7 = 0 - operation success, communication port state, AH bit 6 ~ 0 is its status bit
(3), function 02h
Function Description: Read characters from communication port
Entrance parameters: ah = 02h
DX = Initialization communication slogan (0 = COM1, 1 = COM2, ...)
Export parameters: Al = acceptable characters
AH bit 7 = 0 - operation success, communication port state, AH bit 6 ~ 0 is its status bit
(4), function 03h
Function Description: Read communication port status
Entrance parameters: AH = 03H
DX = Initialization communication slogan (0 = COM1, 1 = COM2, ...)
Export parameters: AH = communication port status, Al = MODEM status, see the description in the function number 00h
(5), function 04h
Function Description: Expand the initial communication port, which is only valid in PS / 2, from this slightly 4, miscellaneous system service - INT 15H)
00h - open cassette machine motor 85h - System Request (SYSREQ)
01H - Close box tape drive motor 86h - delay
02H - Reading Case Tape Machine 87h - Mobile Extended Inclusion Block
03H - Writing Case Tape Machine 88H - Read Extension Memory Size
0FH - Format ESDI drive Regular interrupt 89h - Enter protection mode
21H - Read / write self-test (POST) error record 90h - equipment waiting
4FH - keyboard interception 91h - Device Power-Disk Self-test
80H - Equipment Open C0H - Read System Environment
81H - Device Turn off C1H - Read Extension BIOS Data Area Address
82H - Process Termination C2H - Mouse Graphics
83h - Event Waiting C3H - Set WatchDog Timeout
84H - Read Channel C4H - Programmable Options Selection
(1), function 00H
Function Description: Open Case Tape Machine Motor
Entrance parameters: AH = 00H
Export parameters: cf = 0 - operation success, otherwise, AH = status (86h, if no cassette is installed)
(2), function 01h
Function Description: Touch Tape Machine Motor
Entrance parameters: AH = 01H
Export parameters: cf = 0 - operation success, otherwise, AH = status (86h, if no cassette is installed)
(3), function 02h
Function Description: Reading Case Tape Machine
Entrance parameters: ah = 02h
CX = number of bytes read
ES: bx = buffer address for storing data
Export Parameters: CF = 0 - Operation, DX = The number of bytes actually read, ES: BX points to the back address of the last byte, otherwise, AH = status code, its value is as follows: 01h
- CRC check code error 80h - illegal order
02H - Bit signal confusion 86h - no cassette machine
04h - no data
(4), function 03h
Function Description: Writing Tape Machine
Entrance parameters: AH = 03H
CX = number of bytes to be written
ES: bx = buffer address of the data stored
Export Parameters: CF = 0-- Operation, CX = 00H, ES: BX points to the back address of the last byte, otherwise, AH = status code, its value is as follows: 80h -
Illegal order 86h - no box tape drive
(5), function 0FH
Function Description: Format the ESDI drive periodically interrupt, only in PS / 2, from this
(6), function 21h
Function Description: Read / write self-test (POST) error record, only valid in PS / 2, from this
(7), function 4FH
Function Description: Keyboard Intercept, only in PS / 2, here from this
(8), function 80h
Function Description: Open the device
Entrance parameters: AH = 80h
BX = device number
CX = process number
Export parameters: cf = 0 - operation success, AH = 00h, otherwise, AH = status code
(9), function 81h
Function Description: Close the device
Entrance parameters: AH = 81H
BX = device number
CX = process number
Export parameters: cf = 0 - operation success, AH = 00h, otherwise, AH = status code (10), function 82h
Function Description: Termination of Process
Entrance parameters: AH = 81H
BX = process number
Export parameters: cf = 0 - operation success, AH = 00h, otherwise, AH = status code
(11), function 83h
Function Description: Event Waiting
Entry parameters: AH = 83H If event is required, then: Al = 00H
CX: DX = Mix
ES: BX = Signal volume byte address
Otherwise, the call parameter is Al = 01h
Export Parameters: If you call, Al = 00h, the operation is successful - CF = 0, otherwise, CF = 1
(12), function 84h
Function Description: Read the game
Entrance parameters: AH = 84H
DX = 00H-- Read switch settings
= 01H - Read resistance input
Export parameters: cf = 1h - operation failed, otherwise,
When DX = 00h, Al = switch settings (bit 7 ~ 4)
When DX = 01h, AX, BX, CX and DX are A (X), A (Y), B (X), and B (Y) value, respectively.
(13), function 85h
Function Description: System Request (SYSREQ) button
Entrance parameters: AH = 85H
Al = 00H - button
= 01H - button release
Export parameters: cf = 0 - operation success, AH = 00h, otherwise, AH = status code
(14), function 86h
Function Description: Delay
Entrance parameters: AH = 86h
CX: DX = Mix
Export parameters: cf = 0 - operation success, AH = 00h
(15), function 87h
Function Description: Move extended memory blocks from regular memory and extended memory
Entrance parameters: AH = 87h
CX = number of words moving
ES: Si = GDT (Global Descriptor Table), its structure is defined as follows: Offset storage information
00h-0FH reserved, but now 0
Length of 10H-11H (2CX-1 or greater)
12H-14H24 source address
15h access by 10 (which is 93h)
16h-17h is retained, but now is 0
Length of 18H-19H (2CX-1 or greater)
1AH-1CH 24-bit target source address
1DH access byte (its value is 93h)
1EH-2FH reserved, but now is 0
Export Parameters: CF = 0-- Operation, AH = 00h, otherwise, AH = status code, its meaning is as follows:
01H - RAM odor
02H - abnormal interrupt error
03H - 20 line door address failed
(16), function 88h
Function Description: Read the extended memory size
Entrance parameters: AH = 88H
Export Parameters: AX = Extended memory byout (in K)
(17), function 89h
Function Description: Enter protection mode, CPU enters protection mode from real mode
Entrance parameters: AH = 89HBH = IRQ0 interrupt number
BL = IRQ8 interrupt number
ES: Si = GDT address (see function number 87h)
Export Parameters: CF = 1 - Operation Failure, AH = 0FFH, otherwise, AH = 00H, CS, DS, ES and SS are user-defined selectors
(18), function 90h
Function Description: Equipment Waiting
Entrance parameters: AH = 90h Al = Drive type, the specific drive type is defined as follows:
= 00h ~ 7FH - serial reusable equipment
= 80H ~ 0BFH - reusable equipment
= 0C0H ~ 0FFH - Wait for access to the device, no self-test function
00h - disk
02H - keyboard
80H - Network
FDH - floppy motor start 01H - floppy disk
03H - Point device (Pointing Device)
FCH - hard disk reset
Feh - printer
ES: bx = request block address for drive type 80H ~ 0FFH
Export parameters: cf = 1 - Operation failed, otherwise, AH = 00H
(19), function 91h
Function Description: Equipment Power Expeed Self Test
Entrance parameters: AH = 91H
Al = 00H ~ 7FH - serial reusable equipment
= 80H ~ 0BFH - reusable equipment
Export parameters: AH = 00H
(20), function 0c0h
Function Description: Read the system environment
Entrance parameters: AH = 0c0h
Export Parameters: ES: BX = Configure Table Address, Definition of Configuration Table as follows: Offset Meaning Description
00h-01H table size (number of bytes)
02h system model
03h system subdrane
04HBIOS version number
05H Configuration Sign, the description of the 1 time is as follows:
Bit 7-DMA channel 3
Bit 6 - existence of the subordinate 8259
Bit 5-real-time clock is effective
Bit 4-keyboard interception is effective
Bit 3 - Waiting for external events to be effective
Bit 2- Expand BIOS Data Area
1-microchannel facility
Bit 0 - Reserved
06H-09H reservation
(21), function C1H
Function Description: Read the extension BIOS data area address, only in PS / 2, here from this
(22), function C2H
Function Description: Mouse graphics, only valid in PS / 2, here from this
(23), function C3H
Function Description: Set WatchDog Timeout, only in PS / 2, from this
(24), function C4H
Function Description: The programmable option is selected, which is only valid in PS / 2, here from this
5, Keyboard Service (Keyboard Service - INT 16H)
00h, 10h - Read the character 03H from the keyboard - set the repetition rate
01H, 11H - Read keyboard status 04H - Set keyboard Click
02H, 12H - read keyboard logo 05h - characters and their scan code
(1), function 00h and 10h
Function Description: Read the character from the keyboard
Entry parameters: ah = 00H - read keyboard
= 10h - Read the extended keyboard, can be determined according to the content of 0000: 0496H unit: the expansion keyboard is valid
Export Parameters: AH = Scan code for keyboard
Al = Character ASCII code
(2), function 01h and 11h
Function Description: Read the keyboard status
Entrance parameters: AH = 01H - Check the ordinary keyboard
= 11h - Check the extended keyboard
Export Parameters: ZF = 1 - No Character Input, otherwise, AH = keyboard scan code, Al = ASCII code. (3), function 02h and 12h
Function Description: Read the keyboard logo
Entrance parameters: AH = 02H - Shift sign of ordinary keyboard
= 12H - Displacement mark of extended keyboard
Export parameters: Al = keyboard flag (02h and 12h are valid), the meaning of the value of 1 is as follows: Bit 7-INS Open Status Bit 3-Alt Key Press
Bit 6-Caps Lock Open Status Bit 2-Ctrl button Press
Bit 5-Num Lock Open Status Bit 1 - Left SHIFT button Press
Bit 4-Scroll Lock Open Status Bit 0- Right SHIFT button Press
AH = Sign (12h valid) of the extended keyboard (12h), the meaning of the value of 1 is as follows:
Bit 7-SysReq key Press the next 3-right alt button to press
Bit 6-Caps LOCK button Press 2- Right Ctrl button to press
Bit 5-NUM LOCK button Press the next 1-left ALT button to press
Bit 4-Scroll button Press the next 0- left Ctrl button
(4), function 03h
Function Description: Setup Rate
Entrance parameters: AH = 03H For PC / AT and PS / 2: Al = 05H
BH = repeated delay
BL = repetition rate
For PCJR: AL = 00H - load the default rate and delay
= 01H - Add initial delay
= 02H - Repeated frequency reduces half
= 03H - Add delay and reduce half repeat frequency
= 04H - Close the keyboard repeat function
Export parameters: no
(5), function 04h
Function Description: Set keyboard clicks
Entrance parameters: AH = 04h Al = 00H - Close the keyboard click function
= 01H - Open the keyboard click function
Export parameters: no
(6), function 05h
Function Description: Character and its scan code
Entrance parameters: AH = 05H
CH = character's descriptor code
CL = Character ASCII code
Export Parameters: CF = 1 - Operation Success, Al = 00h, otherwise, Al = 01H
6, parallel port service (Parallel Port Service - INT 17h)
00h - output character to the printer
01H - Initialization Printer Port
02H - Read the printer status
(1), function 00H
Function Description: Output Characters to the printer
Entrance parameters: AH = 00H
Al = output character
DX = Printer number (0-LPT1, 1-LPT2, 2-LPT3, ...)
Export parameters: AH = printer status. The meaning of each time is as follows: Bit 7-Printer Free Bit 3-I / O Error
Bit 6-Printer response 2 - reservation
Bit 5- No Paper 1 - Reserved
Bit 4-printer is selected from 0-printer timeout
(2), function 01h
Function Description: Initialization Printer Port
Entrance parameters: AH = 01H
DX = Printer number (0-LPT1, 1-LPT2, 2-LPT3, ...)
Export parameters: AH = printer status. Did you define the following features 00h
(3), function 02h
Function Description: Read the printer status
Entrance parameters: ah = 02h
DX = Printer number (0-LPT1, 1-LPT2, 2-LPT3, ...)
Export parameters: AH = printer status. Distinguish 7, clock service (CLOCK Service - INT 1AH)
00h - Read the clock "Tick" count 06h - set alarm clock
01H - Set the clock "Tick" count 07h - alarm reset
02H - Read time 0AH - read the number of days count
03H - Set time 0bh - set the number of days count
04H - Read Date 80H - Set Sound Source Information
05h - set the date
(1), function 00H
Function Description: Read the clock "Tick" count
Entrance parameters: AH = 00H
Export Parameters: Al = 00H-- Not over Midnight, otherwise, it means that has been overnight
CX: DX = Clock "Tick" count
(2), function 01h
Function Description: Set the clock "Tick" count
Entrance parameters: AH = 01H
CX: DX = Clock "Tick" count
Export parameters: no
(3), function 02h
Function Description: Reading time
Entrance parameters: ah = 02h
Export Parameters: CH = BCD code format
CL = BCD code format minute
DH = BCD code format
DL = 00H - standard time, otherwise, daylight saving time
Cf = 0-- clock is walking, otherwise, the clock stops
(4), function 03h
Function Description: Setting time
Entrance parameters: AH = 03H
CH = BCD code format
CL = BCD code format minute
DH = BCD code format
DL = 00H - standard time, otherwise, daylight saving time
Export parameters: no
(5), function 04h
Function Description: Read Date
Entrance parameters: ah = 04h
Export Parameters: CH = BCD code format
CL = BCD code format
DH = BCD code format
DL = BCD code format day
Cf = 0-- clock is walking, otherwise, the clock stops
(6), function 05h
Function Description: Setting Date
Entrance parameters: AH = 05H
CH = BCD code format
CL = BCD code format
DH = BCD code format
DL = BCD code format day
Export parameters: no
(7), function 06h
Function Description: Set alarm clock
Entrance parameters: AH = 06h
CH = BCD code format
CL = BCD code format minute
DH = BCD code format
Export Parameters: CF = 0 - Operation is successful, otherwise, the alarm has been set or the clock has stopped
(8), function 07h
Function Description: Alarm Reset
Entrance parameters: AH = 07h
Export parameters: no
(9), function 0AH
Function Description: Read the number of days, only in PS / 2 is valid, here from this
(10), function 0BH
Function Description: Set the number of days count, only in PS / 2 is valid, here from this
(11), function 80h
Function Description: Set the sound source information
Entrance parameters: AH = 80h
Al = sound source
= 00H - 8253 programmable timer, channel 2
= 01H - cartridge input
= 02H - Audio in "on the I / O channel
= 03H - Sound generation chip
Export Parameters: None 8, Direct System Service
INT 00h - "0"
INT 01H - Single step interrupt
INT 02H - Non-mask interruption (NMI)
INT 03H - breakpoint interrupt
INT 04H - Arithmetic overflow error
INT 05H - Print screen and Bound Crossing
INT 06H - illegal instructions
INT 07H - processor extension invalid
INT 08H - Clock interrupt
INT 09H - Keyboard input
INT 0BH - Communication port (COM2 :)
INT 0CH - Communication port (COM1 :)
INT 0EH - Disk drive input / output
INT 11h - Read device configuration
INT 12H - Read the regular memory size (return value AX is memory capacity, K as unit)
INT 18H -ROM Basic
INT 19H - Heavy boot system
INT 1BH -CTRL BREAK handler
INT 1CH - User Clock Service
INT 1DH - pointing to the display parameter table pointer
INT 1EH - Point to disk drive parameter table pointer
INT 1FH - Pointing graphic character mode table pointer
Note: Information comes from "small highlights"
