; Following is a minimal program for sending a sequence of bytes to the
;   PRN printer-device.  The codes that are sent appear in the DB statement
;   following the label CODES.

PRINT_CODES:
  MOV DX,PRN_NAME   ; point to the printer's device name
  MOV AX,03D01      ; MSDOS codes for "open for writing"
  INT 33            ; call MSDOS to open the printer device
  XCHG BX,AX        ; swap the printer's open-file handle into BX
  MOV DX,CODES      ; point to the codes we are outputting
  MOV CX,LENGTH     ; load the number of code bytes
  MOV AH,040        ; MSDOS code for "write"
  INT 33            ; write the codes to the printer
  MOV AX,04C00      ; MSDOS codes for "successful process termination"
  INT 33            ; go back to the operating system

PRN_NAME:
  DB 'PRN',0

CODES:
  DB 0C             ; single form-feed for the PAGE program
LENGTH EQU $-CODES