Click above to get retro games delivered to your door ever month!

  Interrupt 05H (decimal 5) activates the print-screen service: The keyboard
  support routines generate interrupt 05H in response to the Shift-PrtSc
  combination; any other programs that want to perform a print-screen
  operation can safely and conveniently do so by generating interrupt 05H.

  The print-screen service will maintain the current cursor position on the
  screen and successfully print any printable characters from the screen in
  either text or graphics mode. It uses both the standard video services
  (those that waltz the cursor around the screen and read characters from
  the screen buffer) and the standard printer services.

  This service directs all its output to printer number 0, the default
  printer. There are no input or output registers for this service. However,
  a status code is available at low-memory location 0050:0000H. (See page
  61.) If the byte at that location has a value of FFH (decimal 255), then
  a previous print-screen operation was not completed successfully. A value
  of 00H indicates that no error occurred, and that the print-screen
  operation is ready to go. A value of 01H indicates that a print-screen
  operation is currently in progress; any request for a second one will be
  ignored.

  The ROM BIOS print-screen routine cannot print images drawn on the screen
  in graphics modes. If you want to produce a printed screen snapshot in
  CGA-compatible graphics modes, use the DOS utility program GRAPHICS. This
  program installs a memory-resident, graphics-mode print-screen routine
  that hooks interrupt 05H. Once you execute GRAPHICS, pressing Shift-PrtSc
  or executing interrupt 05H while in a graphics mode will cause the
  graphics-mode print-screen routine to run.