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 Using CALL INTERRUPT to Push Characters into Keyboard Buffer - Q50944
 
 It is possible in Visual Basic for MS-DOS to push keys into the
 keyboard buffer on IBM AT and PS/2 class computers using the
 CALL INTERRUPT statement. (This technique will not work on IBM PC
 class computers.) This can allow you to create keyboard macros, such
 as for training and demonstration sequences in a program. Therefore,
 if you were to write a program that required a lot of input from and
 interaction with a user, you could also write a training or
 demonstration sequence that would show the user what kind of input
 your program required, using the method demonstrated below. This
 would require filling in the required responses for the user by
 pushing the keystrokes into the keyboard buffer.
 
 More Information:
 
 The interrupt for the key push routine requires both the scan code for
 the key and the ASCII value of the character to be pushed. A maximum
 of 15 characters can be pushed into the keyboard buffer at one time.
 
 The example program below, KEYPSH.BAS, sets up a table containing all of
 the scan codes for ASCII character values 32 (a space) through 126
 (~), and defines the routine PUSHSTRING that will push the passed
 string of characters into the keyboard buffer.
 
    ◄See Example►
 
 Keyboard scan codes and ASCII codes are documented in Appendix A of
 "Microsoft Visual Basic for MS-DOS Language Reference".