mov ah, 07h ;Direct Console Input
int 21h
mov InputChar, al ;character from standard input
Direct Console Input (Function 07h) reads a character from standard input. If no character is available, MS-DOS waits until one is available. This function does not send the character to standard output.
This function has no parameters.
The AL register contains the ASCII value of the input character.
If the character read from standard input is an extended key code (for example, if the user presses one of the function keys), Direct Console Input returns 00h and the program must call the function again to get the second byte of the extended key code.
This function does not check for CTRL+C.
Function 06h Direct Console I/O
Function 08h Read Keyboard Without Echo
Function 0Ah Buffered Keyboard Input
Function 0Bh Check Keyboard Status
Function 0Ch Flush Buffer, Read Keyboard
Function 3Fh Read File or Device